alright, I believe I've gotten it to work. Somewhat, at least.
note the the outlines on the body, they're tinted correctly now (are black on the texture) the shadow is tinted in the color as well, which isn't great, but I think I can fix it.
The biggest problem implementing this was that the VertexInput struct in "com.esotericsoftware.spine.spine-unity\Runtime\spine-unity\Shaders\Sprite\CGIncludes\SpriteLighting.cginc" didn't implement uv1 and uv2
after that, I followed this post's suggestions: https://esotericsoftware.com/forum/d/14142-urp-2d--tint-black
I hope a proper implementation will be added though. If I manage to get everything working correctly I'll definitely post an update here/github, but as mentioned before, this isn't my forté, so I can't gurantee anything.