Required software development,Website Development freelancer for Watch later playlist job

I need a tool (script/browser addon/desktop program) to download/convert Youtube playlists and 'watch later-lists'.
I've done some Google searching but I couldn't find anything simple enough to use.

If you are able to find something already existing on the internet I would be content with that, otherwise I need the tool to be written/configured to my needs.

I usually use these webistes to fetch each video individually (as mp3s), maybe you could incorporate them into the software if needed:

Are you able to do it?

Skills & Expertise Required

software development Website Development