Created new Apple Music library due to migration issues: will duplicates appear when Sync is turned on?

I had multiple issues come up when migrating my Apple Music library from an old iMac to a new Mac Mini (local ALAC files showing up as Cloud only AAC files, AAC files that don't have file sizes, etc - more info below). I'm creating a new Apple Music library on a separate external hard drive, and have copied all of my music from my prior Media folder into the new library using "File -> Import". Sync is currently turned off. I'm wondering what will happen if I turn on Sync - will I have duplicates of all my files appear (local versions and Cloud versions)?

https://discussions.apple.com/thread/256218757?cid=em-com-apple_watches_email_thread_owner-view_the_full_discussion-en-us-11282023&sortBy=rank