There are some other factors included in the simulations besides the formations that affects a match. Your team may have the greatest formation against an opponent playing with a she1et formation, but you can still have a "bad day" and there are some factors that includes it in game (I feel it could reduce something like 30-40% of your team quality).
Read more about it here: https://forum.topeleven.com/top-elev...op-eleven.html