there is no strong formation. u have to adapt ur formation by analysing ur opponent formation. so if hes playing only AMC,MC,ST just put 3DC and DMC; If hes playing AMR,AML,ST then go for DL,DC,DR or DL,DC,DC,DR and so.. always first try to counter hes ST and midfielders. Then put ur AM's and ST by watching ur opponent DM's and defense. If hes playing DL,DC,DR put 2ST, if hes playing DC,DC,DC put AMR and AML then a ST and so.
There is no REAL formation and UNIQUE formation u have to change every match