Animating Face from Blender to Godot using Bones

Godot Version

4.3 Stable

Question

Hello everyone !

I’m trying to make a 3D lowpoly character, and managed to get everything i wanted this far, including face animation in Blender using a bone, making it usable for the blender animation system, thanks to this video : https://www.youtube.com/watch?v=3fHeWqKpBTc

The gist of it : Using a 2D spritesheet in Blender and the coordinate of my bone, I can change the character’s face just by moving the bone around.

However, in Godot, while the bone still move, the sprite of the face remain unchanged, the bone coordinate doesn’t affect the material anymore.

My model comes from a .blend and is shared in real time from Blender to Godot, and so I ask you people : How can I make my character’s face material change using this same bone in Godot ?
Thanks in advance !