I'm working on a pretty old video game and it's required that I mirror as much as possible in UVs.

The Problem: When broken into efficient mirrors, Substance Painter will bake in artifacts into the normal map because it's baking all on top of each other.

https://drive.google.com/file/d/11U0JriW-ZJ0_r3X5E1Je7rkXvqyCAWOP/view?usp=sharing [drive.google.com]

The Solution: Each mirrored island needs to be placed on it's own UDIM tile.

Here's what my UV mesh looks like, the red are the overlapping UVs, which vary in the amount of times they're mirrored.

https://drive.google.com/file/d/1tDpFA_e7nM5kAHyH_e8tJfLLKsKesKIY/view?usp=sharing [drive.google.com]

So there's nothing in "UV Layout" that I can see that will let me do this easily.

Can anyone think of a good way to accomplish this?

Normally I'd grin and bear and brute force it but this is one of many, many models I'll need to do this to so I need a proper pipeline. Thanks in advance!