Tubearchivist works well for me and integrates with jellyfin.
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You could also setup an API to pull the metadata from YT videos like the description and title from YT directly.
https://github.com/ankenyr/jellyfin-youtube-metadata-plugin
https://github.com/ankenyr/jellyfin-youtube-metadata-plugin
Fixed your link.
I dunno what I copy pastet there but thank you.
I don't know anything about jellyfin so no idea if this actually fits your requirements, but hosting your own invidious instance would give you a YouTube web interface which you could use to watch directly or download for later.
For what it's worth, emby does pull YouTube data in for me, as I have a few YouTube video series in my erm media folder and was surprised it automatically brought the metadata. So jellyfin might have something similar built in.