This is the most recent and performant tool I have heard off, to convert Minecraft worlds to Mineclonia specifically.
https://github.com/rollerozxa/MC2MT
I haven’t tested it though.

Btw, mineclone2 also rebranded as Voxelibre, months ago, and for the same reasons. Voxelibre now actively moves away from copying Minecraft exactly.
If you want the closest copy (and my personal recommendation) check out Mineclonia.

My contribution to the discussion is that the Greek phrase for “(in) my ass”, if said in a hasty/hillbilly way, sounds pretty similar to Gollum. Might even call in to question the true nationality of this game’s visionary inventor.

The standard shell on the steam deck can be a bit creaky if you put pressure on certain points. How’s the new one?