How to change the colour of a mesh that has a texture?

[Takemura]

There are several things that comes to my mind:

1. You use Instances that share material with your original mesh, if you want to set individual materials for each, you have so use Clones:
   Clones | Babylon.js Documentation

2. Your meshes have PBRMaterials, so you will have to set albedoColor.
   Mastering PBR Materials | Babylon.js Documentation

3. You use MultiMaterial, I guess you have to set material of submesh?
   Multi-Materials | Babylon.js Documentation

I.e. if you set MultiMaterial-flag to false on MergeMeshes and set albedoColor it works:

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