It is only suppose to matter in corner kicks

Corner kicks: They are crosses from either side of the opponent’s goal. Your corner kick takers should be right footed for right corner kicks and left footed for left corner kicks and in both cases have high crossing skill. Using the correct footed player is very important, as a plain right footed player will be better crossing a right corner kick than a left footed corner specialist (unless he also has a much higher crossing skill).
http://forum.topeleven.com/tutorials...-opponent.html