Don’t know for sure if its a bug, but I’m quite struggling with the maps from the android version of VRchat. The shader I used for example is bumped diffuse, and when I uploaded it, it was quite odd. Is there a possible way I could resolve this issue
This might not help, but, for quest I don’t usually used the bumped diffuse shader, if all I need is a normal map (and not the additional detail/roughness/smoothness maps), I just use Standard-light.
For PCVR you could use the Unity Standard shader if you only need one texture, with one normal (i.e., not full on PBR shader). Adjust sliders as needed.
To debug I would look at it in the editor, is the same effect shown in the editor? Does the same thing happen on a Windows model? It might simply be the way the normal map imported, then. Try to import again or redo it in blender/etc, make sure Unity set it as a normal map, make sure it has the right ASTC compression, it’s probably something simple.
Also, hate to say it but VRChat on Quest (which is different from Unity’s mobile capabilities in interesting ways) … it just has its limits, the end result may not always appear as expected… have to give it some creative license.