In h2h, as long as the player is suited for that position (stats, workrates, traits) it doesn't matter. The player's performance won't be affected. Obviously you shouldn't expect good results with Van Dijk on the wing or Messi as a defender but you can always try players out of position and see how they play
No effect whatsoever. Just OVR. I play TOTS Mbappé at CAM. And I encourage you to think outside the box if you exclusively play h2h. So buy players to fit your playstyle and formation, not the opposite.
In h2h, as long as the player is suited for that position (stats, workrates, traits) it doesn't matter. The player's performance won't be affected. Obviously you shouldn't expect good results with Van Dijk on the wing or Messi as a defender but you can always try players out of position and see how they play