What does HackerNews think of czkawka?
Multi functional app to find duplicates, empty folders, similar images etc.
But I switched over to czkawka, which has a better interface for comparing files, and seems to be a bit faster: https://github.com/qarmin/czkawka
Unfortunately, neither of these are integrated into Photoprism, so you still have to do some file management outside the database before importing.
I also haven't used Photoprism extensively yet (I think it's running on one of my boxes, but I haven't gotten around to setting it up), but I did find that it wasn't really built for file-based libraries. It's a little more heavyweight, but my research shows that Nextcloud Memories might be a better choice for me (it's not the first-party Nextcloud photos app, but another one put together by the community): https://apps.nextcloud.com/apps/memories
The first one i found and still use when it got obvious that fslint is EOL is czkawka [0] (meaning hiccup in polish). Its' speed is an order of magnitude higher than fslint, memory use is 20%-75%.
<;)> Satisfied customer, would buy it again. ;)>