This was something I wrote about 6 years ago. This was originally more or less for Window XP since it didn’t really have this feature. It never really worked the way I had wanted it to. I decided to go back and re-write it in the hopes that someone may find it useful.
The code as is isn't complete. There are some changes I plan on making (currently it just does jpgs) but as the code is , it works.

I posted the source code to my github which can be found below:
Zero1UP/Wallpaper-Changer · GitHub