pretty sure standard prints should work, i can see the stock plex scanners using them in some places, but it doesn’t look like they show up in the log, to see them run plex media scanner in a terminal. (verbose mode is -v if that helps you too, though for me the prints are showing without it)
Make sure you are looking at the console.app, not the terminal. And AFAIK you have to add a new section to trigger the scan. lots of add section remove section in the debug cycle!