[ocelotpotpie]

We tend to call those "networks", when they have a bunch of different gametypes and servers interconnected. At a smaller scale of a few hundred players it's pretty easily handled by off the shelf software like Velocity for the proxy and a few server instances running Paper.

You generally want good performing (not VPS or "cloud" instances) but you can run a bunch of different worlds and have people with cross server talk, the ability to warp between worlds, etc. Most of the larger networks and nearly all of the smaller networks use a variation of this kind of model.