Its possible, yes. I tested this quite a while ago, so details are a bit fuzzy, but I seem to remember that if a drive that had been set up to be used with Time Machine by a newer version of MacOS (I think it was Ventura), Photo Mechanic couldn't access its subfolders in the Navigator, but then if I went back and set up Time Machine with an older OS, Photo Mechanic had no problem with it, even if I then connected that drive to a newer version of MacOS. If I can locate my previous findings, I'll post them here.