cuberite VS Leafish

You might be able to port a C/C++ implementation to Arduino or another language with a good ESP compiler, but that's going to be a lot of effort, and the biggest challenge you're going to face isn't RAM, it's disk space--Minecraft worlds can be GB in size, so you'll need to pair your microcontroller with, say, an SD card reader and then adapt a whole disk IO system

Shout out for Cuberite as an alternative Minecraft server project that desperately needs more volunteers

https://github.com/cuberite/cuberite

"Cuberite is a Minecraft-compatible multiplayer game server that is written in C++ and designed to be efficient with memory and CPU"

Cuberite has been demoed running on old ARM Android phones and hosting multiple players off it at once. Its performance absolutely annihilates the Java based 'vanilla' server

so basically Cuberite but more officially and with a rewritten client as well

Some have started doing this already, like Cuberite and McPy.

For minecraft server I guess it is worth trying this out: https://github.com/cuberite/cuberite

For the server you should look into Cuberite, same thing but for the server and written in C++.

There were a bunch of attempts in the past. Cuberite is still actively maintained but I have never tried them: https://github.com/cuberite/cuberite

There has been some work... feather mc server and piston's hematite client This client also seems to be in active development: Leafish

and https://github.com/Lea-fish/Leafish a fork of it

This isn't the first project like this so I'm guessing it's fine. https://github.com/Lea-fish/Leafish

Check out Leafish if you have an issue with that like I do