Material World position offset and Normals

Hi,

I want to recreate this effect on UE4:

I have created a new material and I am using the World Position Offset to deconstruct the mesh based on its vertex normals. Right now I am viewing the material on a Cube and this is the result so far (very simple)

https://preview.redd.it/84ahy0yrjby41.png?width=252

As you can see, the cube is deconstructed but not its faces (which are composed by two triangles each).

In order to deconstruct its faces, I want to apply a random vector offset depending the triangle/face.

Is this possible? Should I change my approach? Suggestions? Help.