Thank you so much for your ideas!
I’m still not sure which solution to go for. It would make sense to just move everything but the player’s ship but you would also have to make everything, and I mean really everything, including other ships, planets, stars, asteroids, projectiles, etc. move and also rotate around the ship. Now if you want to have multiplayer all of this would need to be handled independently on each client because other players would need to be moved around in my client but from their point of view they are standing still and I am the one who needs to be moved around. And I would definitely need a quite experienced programmer for that.
I’ll try the “fake window” solution as it sounds easier. Maybe I could just “hide” the ship somewhere and have an exact copy flying around with cameras attached instead. That would mean that other players could still see your ship even if your character is actually in a copy of your ship somewhere else. That only has the disadvantage that I could probably no longer implement the planned feature that you can destroy other ships’ walls and have their crew sucked into space. But I can’t have everything, right? 