Players learning new positions

[unkempt nebula]

So many career modes I signed players that would be perfect for my team but they were out of position and it’s suck I think it would be so cool for players learn new positions but like a offensive player Learn LW ST RW RMF and etc Defensive player learn LF RB DC DMF and etc

[sullen elm]

Already asked.
The answer is, it's not technically possible.
But nevertheless, it doesn't really matter.
As long as the player has required attributes, they can play well in any position.
Here's the example.
He's played as striker.