LidaTube - Get missing albums from Lidarr and download via YouTube (yt_dlp)
https://github.com/TheWicklowWolf/LidaTube
SpotTube - Download a Spotify playlist via YouTube (yt_dlp)
https://github.com/TheWicklowWolf/SpotTube
Syncify - Sync a Spotify playlist via YouTube (yt_dlp)
https://github.com/TheWicklowWolf/Syncify
These are just some basic apps that may be useful. Also apologies if you’ve seen this before, there were some account-related hiccups etc.
LidaTube seems elite, since the app is in Python you can try to add Scheduling task to run every x hour -> pull missing songs -> convert and save.
Starting Point