hey dont know if you are aware of it already but vertex colors dont seem to export correctly.
cel shaded games often rely on vertex colors like FighterZ or Kakarot.
While modding both of those games i noticed that vertex colors wont export correctly.
For FighterZ we noticed that the R and B channel gets swapped. Manually swapping those fixes the celshading.
Here you can see that they indeed get swapped in umodel.
For Kakarot swapping those 2 channels doesnt fix the shading which lets us think that there is more wrong than just the r and b channel swapped.
here is how it looks in the vanilla game
and this is what we get when we export the model with umodel and just reimport it in the game
would be nice if you could check on vertex color export again as this would greatly help many modding communitys