I'm using nvidia right now with a 3060. It doesnt use much power, I got it for pretty cheap on ebay, and it encodes/decodes everything except for av1 encoding which I dont have use for. Looking at the charts in the link below, if you need to encode av1 you'ld need a 4000 series.
I've found nvidia to work pretty well for jellyfin, I use docker with the nvidia container toolkit and it just worked with hardware encoding out of the gate. I also have some other docker containers running gen ai and the 3060 handles them well as long as the modle will fit in vram.