I am setting up my first jellyfin server via docker, and I am offered the option to either use TMDB or OMDB. I have jellyfin on a LAN-connected device w/o VPN connection, and I am concerned queries to those DBs with file names of torrented files can get tracked and reported to my ISP. Could that be the case? And if so what to do about it? Are there more privacy-preserving metadata services than others?
Firstly connections to those API should be encrypted, so parameters such as the filename shouldn’t be visible by a MitM. Also, as someone else pointed, you could rename the file beforehand to something neutral.
Another alternative is run Jellyfin and all of your *arr apps as docker containers and run them through a docker container called gluetun. Essentially this will route all incoming traffic (tvdb, torrents, etc) through a vpn and all outgoing (sonarr, Jellyfin, etc web gui) can be accessed locally.