I found that the files getting stuck had 644 permissions in contrast to the rest, which had 755. While Apple has a specific permission reset instructions article available, my experience it didn’t help. One issue that may be causing files getting stuck in Onedrive for Mac’s upload queue is wrong permissions. As this is a silent crash, you won’t even be aware that your files are not being synced at all uploading files correctly, at least some files appear to get stuck in the upload queue.
The main issue I’ve been struggling with is that OneDrive will stop working after some days – it will just crash without any warning soon after the app loads.