I'm not OP, but yes it is possible to import arbitrary music into the Apple Music app with whatever cover art and other metadata you want. It's as easy as drag

I'm not OP, but yes it is possible to import arbitrary music into the Apple Music app with whatever cover art and other metadata you want. It's as easy as dragging in a folder of normal, tagged FLAC or MP3 files and it will use the metadata in them to group into albums etc. It's also user-configurable whether the app will move your files into its folder and organization scheme or just leave them alone where you put them.