This seems like a relatively easy thing to code oneself, or for someone to have already made somewhere (relatively easy, just writing something for yourself command line doing it, assuming you can spend a work week of nights [worst case, based on my working with images in folders in the past I think 10 hours for something that works, reasonable time for coffee and other breaks])
Yeah, there are probably a few multimillion dollar app ideas in here, but of insufficient complexity or lowbrow-ness for the typical HN reader (myself included). The nano-banana template idea or the Q&A Walkman, for example.
