okay, I thought that you may be able to hold the MG-42 standing you can in wolfenstien
Going by games, you can fire it standing in Red Orchestra, and that's one of the most realistic WW2 FPS ever.
With the MG-42, I was more thinking of the kickback that would prevent you from firing standing up but whatever.
It would prevent you from firing as accurately, but I doubt it would be a huge problem at mid-shot range.