Holy fuck, how did I not know about this before?

So by sheer accident, I stumbled across an easy-to-use automatic image stitching program that Microsoft put out back in the day (and have since thrown out of support, because god forbid they don't make money). It's called Microsoft Image Composite Editor. And where did I find it? A fucking JoJo Wiki article about stitching:
>https://jojowiki.com/Blog:How_to_Stitch_Anime_Shots#Method_A_-_Automatic

I love the internet, sometimes. Here's an example of a diagonal stitch it produced.

Anon from >>8559853 in case you're still around, Microsoft ICE might be exactly what you're looking for.