I add all videos that I want to watch to a playlist and then run a script on my machine to download the videos. It will only download each video once as it keep tracks of downloaded videos through the file downloaded.txt so you can delete/move them freely. You can also add the script to a systemd timer or cron so to automate it.

This is the script: https://github.com/danisztls/yt-assistant. AFAIK the same can be done with a single line yt-dlp command and you can do the same to download all videos from a channel.