Have you played Outer Wilds? It’s kind of a walking simulator in the sense its 's heavy on discovering the lore and exploration instead of action and defeating baddies BUT it has space flight realistic physics and a solar system simulation. It’s a pretty nice and chill game with space exploration and a constant feel of dread when you step out of the ship but it does not have multiple ships or multiple alien forms. Still, it’s the best game I played recently.