Below is an LSL script you can drop into a prim.
When you touch the prim, it will loop through all faces and report the texture UUID applied to each face, effectively telling you which material (texture) is on which face.

// Material Faces Detector Script
// Reports the texture UUID on each face of the prim when touched

default
{
touch_start(integer total_number)
{
integer num_faces = llGetNumberOfSides();
integer i;
for (i = 0; i < num_faces; ++i)
{
string texture = llGetTexture(i);
vector scale = llGetTextureScale(i);
vector offset = llGetTextureOffset(i);
float rotation = llGetTextureRot(i);

llOwnerSay(
"Face #" + (string)i + ":\n"
+ " Texture UUID: " + texture + "\n"
+ " Scale: " + (string)scale + "\n"
+ " Offset: " + (string)offset + "\n"
+ " Rotation: " + (string)rotation
);
}
}
}
Create a prim inworld.

Edit it and drop this script into the contents.

Touch the prim.

The script will say to you (owner) a list of faces with:

Texture UUID

Scale

Offset

Rotation

This helps you:

Identify which textures are applied on each face.








Confirm if different faces have different materials.


Note

LSL doesn’t give PBR materials (metalness, roughness maps) via script yet—only the diffuse texture.

If you’re working in OpenSim with PBR materials, you’d need to use viewers or database inspection to get more detail.

You could try regions listed on here that have a script library too. One that's not listed is Never Village. There's a brilliant script guy on there - Ares Halostar. His shop on Never Village might have some boxed scripts or just go to the grid and look up his profile. I suspect he's someone who might know where to get this or have it.