[hapticmonkey]

Google Streamer has hardware AV1 support, although I’m unsure if it can direct play with Plex.

AppleTV with Infuse can direct stream and software decode AV1 at 4K 24fps. Not sure about AV1 HDR though.

[breve]

VLC also works on Apple TV: https://www.videolan.org/vlc/download-appletv.html