I use yt-dlp & jellyfin for this exact purpose.
Navigate to the channel you want, then click on the playlists link, this way it breaks the channel into consumable chunks. I use the naming options as channel/playlist/video title. I have yet to solve for pictures to automatically be pulled at the channel level. I also took some of my plex media libraries and split them out. Now in jellyfin I have their yt channels, TV shows, and movies curated on their tablets. I also have the directories shared with plex as every other device I have was already setup with plex and can see the same media.