Devs Blog: The Skills Bible
I hope this helps people in finding out specifically what each skill does.
Have a good read.

Field Player Skills

Crosses

How well you can cross.
> Specifically it controls the direction of the cross. Low crossing means greater chance of crossing to a point far from that which you’ve decided to cross to.

Dribbling

How well you can dribble past other players.
> Used in the dribbling vs. tackling formula. Having a higher dribbling skill than your opponent will increase the chances of winning the dribble.

Tackling

How well you can tackle other players.
> Used in more than one area:
* Used in the dribbling vs. tackling formula. Having a higher tackling skill than your opponent increases the chances of winning the tackle.
* When two players are at the same control zone and a ball reaches them, a formula is used to decide who takes control the ball. Tackling is one of the skills used in this formula.

Short Passes

How well you can pass to a player near you.
> Specifically controls the direction of the pass, if the receiver is nearer than roughly 1/3 (one third) of the width of the pitch from you. Low short passes means a greater chance of passing to a point far from that which you’ve decided to pass to.

Long Passes

How well you can pass to a player far from you.
> Specifically controls the direction of the pass, if the receiver is farther than roughly 1/3 (one third) of the width of the pitch from you. Low long passes means a greater chance of passing to a point far from that which you’ve decided to pass to.

Technique

How well you can control the ball and send it in the right direction after an action.
> One of the most widely used skills in the match engine, it affects various things:
* During shooting at the goal, technique controls the height of the ball. A low technique skill means a greater chance of kicking the ball very high.
* During shooting at the goal, technique also controls the direction of the ball. A low technique skill means a greater chance of shooting wide.
* During running with the ball, technique affects how well you dribble the ball to the right direction. A low technique skill will in most cases make players “zigzag” a lot more when running with the ball.
* During crossing, technique affects the height of the ball as it does during shooting.
* During passing, technique also affects the height of the ball, as it does during crossing and shooting.
* When trying to receive a ball, technique affects the range of the player. A high technique skill allows players to control the ball in the limits of their control area.
* After receiving a ball, technique affects the time the player takes to take full control the ball, if the player received the ball either with his chest or foot. A low technique skill will mean the player will be forced to lose other skills if he attempts a first time action, or take more time to fully control the ball.
* When two players are at the same control zone and a ball reaches them, a formula is used to decide who takes control the ball. Technique is one of the skills used in this formula.

Game Vision

How well you can judge what is happening around you and evaluate the current flow of the game, and how far you can see in the pitch.
> Another widely used skill, it affects various things:
* During passing and crossing it affects the perception of how probable it is for the ball to be intercepted. The higher game vision is, the better the perception.
* When a player is deciding where to run to with the ball, game vision affects his decision. A low game vision skill will mean a greater chance of the player deciding for a zone other than the optimal.
* Game vision directly affects how well a player has perception of other players’ positions in the field, and can delay that perception by an amount of time, causing the player sometimes to not be well aware of the players surrounding him, or to miscalculate their positions.
* A player in a good or dangerous position will sometimes call for a pass; low game vision means the player sometimes will not be aware he is offside and still call for a pass.
* When deciding to pass, game vision will affect your player’s perception of if other players are offside or not.
* When deciding to pass, game vision also affects how well you judge the quality of the pass. A low game vision skill increases significantly the chance of missing good pass opportunities in favor of worse ones.
* It affects the distance you can see in the pitch during various processes. A low game vision skill limits the maximum distance, causing poor judgement in most cases.

Finishing

How powerful your shots are, from a short distance.
> Used in the shooting phase, it directly affects the power of the shots, if they were made with the feet.

Long shots

How powerful and accurate your shots are, from a long distance.
> Used in the shooting phase, it affects the power of the shot, as well as the height of the shot (used together with technique).

Heading

How good your player is at heading the ball.
> This skill is used in various areas:
* When two players are at the same control zone when a ball reaches them, and the ball is high, heading skills are compared using a formula to decide which player wins the ball.
* When shooting or passing, if the ball is high, heading is used instead of the other appropriate skill (if the ball was lower). The speed of the ball after the action is also affected, meaning the ball reaches lower speeds if the action is performed with the head.
* Heading directly affects how high a player can reach the ball. A lower heading skill means the player will not reach very high balls.
* Heading affects how well a player receives the ball if it is high and how much time he takes until he controls the ball fully (like technique when the ball is lower). It also affects first time actions in the same manner as technique.

Positioning

How well and how fast your player positions himself in the field.
> Another widely used skill:
* When trying to control the ball, if the ball is faster than the normal control speed, positioning will make your player try to come in the way of the ball. A low positioning skill means a greater chance of the ball going past him.
* During player movement, positioning is the speed of the player when he’s not chasing the ball or an opponent.
* During player movement, positioning is the time the player takes to decide for another action, if he hasn’t completed the current one and the current one is not the optimal one.
* When two players are at the same control zone and a ball reaches them, a formula is used to decide who takes control the ball. Positioning is one of the skills used in this formula, and the one with the most weight.

Speed

How fast your player is when chasing something or running with the ball.
> Used in two areas:
* A player with high speed skill reaches higher speeds than a player with low speed skill, when trying to reach a ball, run with it, or chasing an opponent.
* Speed controls the top speed you can get before it is considered you’re sprinting, and therefore before depleting your stamina and causing higher fitness losses.

Goalkeeper Skills

Handling

How good the keeper is at controlling the ball after a save.
> The higher this skill is, the less likely your player is to release the ball after saving it, and the better he is at controlling balls coming at higher speeds.

Out of Area

How fast the keeper is when not performing saves.
> Similar to the speed of players, this skill affects the speed at which keepers move when not performing a save.

Reflexes

How good the keeper is at reacting to what’s happening.
> This skill affects two things:
* A keeper with high reflexes will start saves earlier than a keeper with low reflexes. Specifically a keeper with high reflexes recognizes a dangerous ball at higher distances.
* After an incomplete save, a keeper with low reflexes will take longer to recover until he can perform another save.

Agility

How wide the keeper range is.
> Affects two different things:
* Agility directly affects the keeper’s control zone, a keeper with low agility will not be able to get as far to a ball as a keeper with high agility.
* Agility is the speed of a keeper during a save. A keeper with high agility is able to move much faster during a save,

Throwing

How good the keeper is at passing the ball.
> This skill replaces all passing skills when the keeper is making a pass.

General Skills

Stamina

How much time your player can run before he starts getting tired, and how well he deals with fitness losses.
> Used in different areas:
* When sprinting, a player with higher stamina will handle top speed for longer before starting to get tired. This doesn’t affect keepers.
* During the half-time period and after the match, players with higher stamina will recover more fitness than players with lower stamina. This particular bit also affects keepers.

Nino: Low agility reduces his field of play, low handling maximizes the ratio of incomplete saves, low reflexes makes him move slower during saves, low out of area makes him move slower during all the other moments.

Adm Nino: The IO “hold up the ball” should in fact force easy passes to open players instead of risky upfront passes. Opposed to v2 where it is rather useless.

ADM-Nino Muniz:

LS do not depend on finishing.

When a player shoots at goal, one of two skills is used to calculate the shot strength: finishing (if the shot is made inside the area or in the neighborhood of it; or LS, if the shot comes from farther away.

I’m going to make the line that defines that a shot uses either LS or finishing into a circle around the goal, and I’m probably going to make the distance smaller so LS’s will bear even more importance in 2.5. Shot speed will be reevaluated too.

Does stamina have any effect on positioning?

Nino: yes it does!

Nino:

Players with higher game vision are unlikely to pass to players that are offside. Lower game vision can lead to such mistakes. When a player makes a pass, he will evaluate the position *at that moment* of the player he’s passing to.

Nino about positioning in ME v.2.5:

Players with greater positioning react faster to changes on the pitch. A forward with low positioning will be more likely to be caught offside.

This is a change for 2.5: positioning not only is the speed players move without the ball, but also the speed they react to changes. A player with higher positioning is much more likely to be well positioned in *all situations*.

Nino: Acceleration is exactly the same for all players (for now). A player with greater speed skill can only reach higher speeds than players with lower speed skill, but he will accelerate at the same rate as any other player.

ADM-Nino Muniz: Was the pass really perfect? What we see sometimes is that the pass IS received by the intended player, but clearly not in the place it should have gone to in the first place.
And, the LP and SP skills (and mostly every other that plays with possible mistakes) only reduce the posibility of something going wrong; things can go right even with low skills, although I must say there are low chances of that happening. It’s like the common misconception that a 20 dribbler always beats a 18 tackler or some ridiculous thing of the sort I’ve seen thrown around these forums. Being a 20 minimizes the chances of something going wrong, although it can happen; being 0 maximizes the chances of something going wrong, but you still can get it right.

You guys have no possibility of seeing this given that most players are pretty average in terms of skills right now, but believe me, a match between full-skilled players (everything 20) plays a lot different than a bot vs. bot match.

quoting:

In the way ME works now, having 18-20, doesn’t learn you to do something but to have a less chance of making a mistake In this model a player starts from 1 and can get at most to 2.

ADM-Nino Muniz: Although that’s true to some skills, to others it is not. Being 20 in some skills makes it impossible to do mistakes, i.e. you’ll do exactly what you’re supposed to do (in the code) without any random variables.

ADM-Nino Muniz: Yes, an 18 dribbler can beat a 20 tackler.

ADM-Nino Muniz: Technique control the hight but not in that way; in SP it makes your pass go near the ground yea, but in LP it makes the pass go in the correct height to reach your teammate. Low technique can cause the pass to go too high, or too low.