I want to give you some advice: Use Jellyfin, not plex. It has far deviated to a "hub" for other streaming services and unless you want to have built-in streaming platforms on your home media server, or have plex's own "live tv" service shoved up your rear, I would steer clear.
Jellyfin is pretty lightweight if you're just streaming 1-2 connections at a time, I ran it on a raspberry pi 4 for a while and it was near flawless, only recently have I made a proper VM setup for it.