Power Photos app removes duplicates I need to keep when copying photos to a new library

I have a pretty large photos library (over 20,000 photos), and as I inevitably knew that I would, I ran out of space on my hard drive. I have an external hard drive already, and I'm looking to move my library to live only on the external hard drive to free up space on my computer's.

Because of the size of the library I wanted to organize it better, and create individual libraries for each year, and for certain events. I also figure this will help avoid any issues with it getting stuck while copying such a large number of pictures, if I'm not trying to do all 20,000 at once. I created albums that represented what I wanted the new libraries to be (one for each year) and put all those photos from that year in.

The issue I'm having is that when I copy the photos from the albums into the new libraries on my hard drive using the Power Photos app, it removes all duplicates. For most people this would be desired, however, although I do sometimes use outside applications, I edit many photos simply using the photos editing tools since I usually only want a few light and color adjustments. Before I edit a photo, I always duplicate it and edit the duplicate so that I have the original, and if I decide I don't like the edit or I want to consider a different way to edit it I still have the original image to use for those purposes. Whenever Power Photos removes all of the duplicates, it removes the photos I've edited, which I obviously don't want.

Is there any way around this? I tried removing the "version 2" title from a duplicate and that did not work, and I thought that renaming the duplicate photo may work but I can't find where to rename an image in photos.

This isn't ideal and I can't guaranteed it working in this case, but this is the roundabout solution that I go for when I want to stop any given OS molesting my files: Zip it. If you put the files that Power Photos is deleting in to a zip, move that zip to the external drive, and then uncompress (unzip), you should end up with the duplicates on the external drive. If you can then copy the unzipped files in to the albums that you want them to be in, your problem should be solved.

Also, are you sure that PowerPhotos is the right tool for this job? I commonly see it deleting duplicates advertised as a feature, rather than as something that you're supposed to avoid.