Basically the title. I'd like to take the overworld from a old save and add it as another dimension in my new world. Is that even possible, and if so how would one go about doing that, or where might a guide or video or something to help be located?
I've tried adding a dimension via datapack, but the ability to define a separate seed for another dimension was apparently removed. I've also looked at other dimension mods like multiverse, but they are all stuck in older versions of MC.