Exporting OBJ with multiple materials for the same face.

Hello everyone,
I have some 3D models for a videogame, in order to place some textures on top of another for achieving effects in the game engine. I need to export an OBJ model with multiple materials for some faces, I’ve made a little research and I’m not sure if you can do this in Blender. I’ve seen objects with multiple materials, but each material is applied to different faces of the object.

I’ve tried to do it myself but failed, the object is exported with just one of the materials.
Can you do that using Blender? Any link on how to do this?

Thank you!

A face can have only one material.
A material can have multiple textures
A texture can consist of a video or a sequence of images
You can animate a texture moving across the UV space to change the image under the faces UV

Whether any can be exported to .obj and/or work in your target application you’ll have to experiment with