I have a Synology NAS, JRMC19 for Mac and a Mac Mini which mounts the Music Folder I use for all my music from the NAS on boot up. Most current version of MC x.103.
I created a new folder under my Music Folder called TestMe.
I then went into MC and configured Auto import.
Configure Auto Import -> I selected the new folder TestMe (which was empty) and clicked finish.
MC then went about analyzing my existing files.
After that was complete I dragged a new album into the TestMe folder. MC was playing music from my NAS at this point.
Within 5 minutes it had imported the new album into my system. Now what it did not do is I had set the option to Get Cover Art set and it did not import the cover art which I had to do manually. In other words after the import I selected Get Cover Art and it was able to locate the Cover Art from the Internet.
So far only tested this with one album.