That's pretty close to how the Machineries and Locked Tomb one on my list works! Honestly, most lost colonies/space empires ones can be crossed over this way pretty trivially, because space is very very big, unless they have canon timeline issues that make it not line up, too many contradictory details about Lost Earth, or extremely incompatible technobabble.

With Firefly I could never quite figure out for myself if it was really supposed to be set in just one really big solar system with a whole lot of settled planets, but if it is, you can slot it into pretty much any space fandom as just one solar system that the main characters had never bothered to visit before.