Answer by knoggly

Thanks for your answers, perhaps one point was not clearly state by me. I don't want the players to choose the keys and buttons. I'm totally fine with defining them myself. But I want to have a defined set of "controllers" the players can choose of (eg. Keyboard1 -> WASD-Keys, Keyboard2 -> UP/DOWN/LEFT/RIGHT-Keys). My problem is connecting the defined Axis in the InputManager to my player-logic, where I have to descide if the current Input was meant for the player.

something like

if(playerNum==1)
{
  value=Input.GetAxis("Player1 left/right");
}
else if(playerNum==2)
{
  value=Input.GetAxis("Player2 left/right");
}

seems quite unelegant for me, but maybe thats the way to go

cheers knoggly