I use qbittorent through Mullvad using Gluetun as qbt is running in docker.
DHT and PEX don’t seem to work though, I did brief research and it seemed related to mullvad no longer allowing port forwarding? I don’t know enough about how it works but I tried messing with it for several hours a couple days ago to no avail, only trackers appear to work for connecting to other peers.
On a headless Ubuntu LXC running in proxmox, I just access the qbt interface via its Web portal.
Matrix