I want to run the Nether and Overworld on separate servers connected via Bungeecord/Waterfall as a workaround for Minecraft's single-threaded performance. I've done this sort of thing before and I've already synced up all the necessary information between servers. This time, I am running into two problems.
Nether portals, previously I had predefined portals that would teleport players as soon as they entered a predefined zone, but with nether portals which are always being created and destroyed, I can't do that.
I need to calculate where the portals will end up and replicate vanilla portal behavior. I know Java and have some experience with Bukkit/Spigot/Paper but I'm not sure where to start in making a plugin for this.
I can't find a way to disable the Overworld on my second server, this can be resolved by teleporting players after they've been sent to the server but it's not an ideal solution and changing the generation to match that of the nether affects the spawning of mobs.
I'm pretty skilled with computers and general and I can do a little bit of Java programming, but don't worry about throwing something a little complicated at me. I just need some solutions and ideas (though I would prefer using already existing software or plugins instead of writing and maintaining my own). This is a repost in a different section, as my question(s) don't exactly fall under one category.