Macs on the same network /Apple ID sharing iTunes music/playlists

In itunes on an iMac I can view my other Macs' Apple Music playlists & libraries. The little drop down list in top left. The red arrow is a different MacBook's Music app.

At the bottom right, there's the option to show everything or only 'songs not in my library.' And - what I most want now - is then import those 'songs not in my library.'

In Apple Music (my own mp3/m4a files, not the subscription streaming) is there a way to use such a feature?

Clearly iTunes can recognise a 'Music' to view/share/import, but can I not do this 'Music' to 'Music'

I see home media sharing in settings, I have that on, but can't connect my Apple Musics (on new Macbook Pro & Air that no longer are itunes.)