I run transmission on a headless box and only open the remote GUI for it once in a while. Can other bittorrent clients do that out of the box?

Yes, probably most of them

Names? :)

franga2000 2 days ago | parent | next [-]

Deluge, QBittorrent, rTorrent, uTorrent have web UIs. Deluge also has a remote mode in the desktop app.

	▲	nottorp a day ago \| parent [-]
		Well when you say "web UIs" i think of another tab that will expand to 4+ G ram if left open long term...

qbittorrent has one, https://wiki.archlinux.org/title/QBittorrent (search “web interface”)