(1.20.1) Are there any mods that add structures similar to Undermod?

Theres a mod called Undermod that adds some really interesting structures, however theres one problem… It causes like a million bugs everytime I try to use it, either making my game crash or massively slowing it down. The main structures I want to replicate are the sewers and giant craters. The creator is apparently patching bugs, but the mod hasn't been updated since the 1.20.1 release, so I'm not too confident in seeing a solution anytime soon.