I've found these two links in their docs, they might be of use:
NextPVR
Provides access to Live TV, Program Guide, and Recordings from
https://github.com/jellyfin/jellyfin-plugin-nextpvr
Antennas
Takes your tuners in TVHeadEnd and emulates a HDHomeRun, in order to connect to Jellyfin's Live TV and DVR features. It requires additional setup and configuration, but is a useful alternative to the TVHeadEnd plugin.
https://github.com/TheJF/antennas
The following links are 3rd party plugin repos, which were obtained from a reddit post, and I haven't visited them yet. Expect questionable code at best:
LazyMan: Play NHL & MLB games through Jellyfin
https://raw.githubusercontent.com/crobibero/Jellyfin.Channels.LazyMan/master/manifest.json
N0tflix
YoutubeDL: Youtube-dl API for recieving streamable links ComedyCentral: WIP plugin to provide Comedy Central content Crunchyroll: WIP plugin to provide Crunchyroll content NRK: Plugin to provide content from NRK web tv Pornhub: Plugin to provide content from Pornhub Redtube: Plugin to provide content from Redtube
https://github.com/n0tOdd/n0tFlix