Current workflow in unity can't be widely used, and not working with other shaders. The live link plugin should just stream textures to a specific path, no need to send mesh from unity first.
So I can open an existing spp file, then streaming textures to any location I want, I can manually assign textures in any materials with any shader, I can use this workflow with maya, 3ds max or blender, too. And no need a maya, 3ds max or blender plugin, because we just stream textures, assign textures can be done in dcc manually.