WDYM by “add more AV1s to my jellyfin”?

As in have AV1-encoded source files and have jellyfin transcode from AV1 to more compatible formats or to have jellyfin transcode existing videos (no matter what format) to AV1 in real-time?

For the former, you shouldn’t need any special GPU whatsoever as a CPU can decode AV1 just fine but a GPU capable of AV1 decode could help. That’s Ampere, Navi 2 and tiger lake or later.

The latter isn’t very useful right now as a device capable of decoding AV1 must be quite modern and those are usually in a position to just decode the original without any need for any transcoding.