Sorry for late reply. On CraftBukki there is a plugin called UltimateWorldGenerator but its a CraftBukkit plugin.I was wondering if there is Custom World Generator like that but not the BetterGen plugin because it's super slow...right now I generate the world in CraftBukkit and then import it on mcpe and convert the ID's with a plugin that I made. The thing is that I have to pre-generate all the chunk on CraftBukkit