Amulet-Core VS Amulet-Map-Editor

I used a small program I wrote a while ago to generate the CA : https://github.com/tterrasson/crystal . Then I generated a random map in Minecraft et used this library to integrate the CA inside the map https://github.com/Amulet-Team/Amulet-Core . I simply assign each state to a type of block (1 to grass, 2 to water etc.) and voilà :)

Edit: AmuletEditor: https://www.amuletmc.com/ Plugin to edit NBT: https://github.com/PREMIEREHELL/Amulet-Plugins/blob/main/EntitiePlugin_nbt_edit.py

There were a few projects that continued working on it. One of them, “MCEdit: Unified”, was supported until 2019, but I don’t believe it supported the MC 1.13 Block ID formats. The team remade it for newer versions and named it Amulet for MC 1.12+.

You can use Amulet to delete chunks that you don't want, and it seems to work with both Java and Bedrock worlds.

Try exporting your map then using Chunker to convert to .mcworld. If your world size is too big for it, try Amulet Editor. instead.

Use a map editor like Amulet to delete unused chunks of the map.

I’m not too experienced with it, but you can try to use amulet to try and edit the nether chunks

https://www.amuletmc.com It's pretty easy to use and it does offer the option to change biomes for selected chunks, as well as trim worlds etc.

If you have that, you can use Amulet to copy the chunks to a new world. Amulet also offers a feature that might be a better option for you. It will let you select chunks to save, then delete all others. This lets them regenerate with the new features included.

MCEdit is not compatible with worlds newer than 1.12.2. Some of the developers moved on to Amulet, though I'm not sure how feature complete it is.