I don't use wingers anymore but when I did only my left wingers seemed to perform well? I would normally put them in the attacking mid left position set to -winger attack. Managed 16 assists and 4 goals in 1 season which is not to bad.
However now I use a 4-1-3-2 narrow with no wingers and am doing alot better with this formation.
Playing the wingers more advanced then my central midfield. The game calls this 4-2-4 but to my mind it's 4-4-2 attacking. Getting some good results with it at Villa with Modric and Milner chipping in a fair few goals. They're just set to winger attack instructions.