False 9 ( AMC instead of a ST)

Hello everyone, if we use a AMC instead of a ST in any one striker formation, does it count as an illegal formation or can we do it?

You will have a small ball possession penalty.
You can try that but at some point the game will punish you.

Thank You :)

I'm using "fake 9". Just make sure you sub the ST in the start of the 2nd half and you'll be ok.
This requires some mentality tweaks as well :)

Red Alert = 2% bonus possession penalty, Yellow triangle = 1%

Using one player there shouldn't be any problem, more often the benefit coming from the player OOP is higher than the penalty itself -Ive played almost all my seasons with 1 player out of position, ST as AMC with a 4-3-3 switching to 4-3-1-2, STs playing as AML/R... MCs as AMCs etc
Just try to don't have more than 1 player with alert if posible.