[AchillesPunks]

I use artwork downloader addon from our friend @Angelinas for local library. It serves me very well. Try it if you haven't already.
https://github.com/Angelinas1/script.artwork.downloader

I already have it but it never saves the artwork to my movie folder or to Kodi. It's always having a skin helper error.

A vast majority of the pieces Artwork Beef collects should be collected by TMM, but TMM ignores yet I can enter manually

Just make sure you add animatedposter to additional artwork types in artwork beef if you have them. Save it to your whitelist