Is it possible to edit face/faces of an FBX object and get the surface properties so you can align/place textures?
If you have a modeling software program like 3ds Max, Maya, or Blender you can import the .FBX and create a Sub/Multi Object material. This options allows you to apply multiple materials to a mesh by assigning material i.d.'s to each face of the mesh.
Once you assign the material i.d.'s you can then export and re-import the FBX, and assign specific materials to the i.d.'s you created.
Let me know if you are having trouble doing this, or if you have some other questions.
“Once you assign the material i.d.'s you can then export and re-import the FBX, and assign specific materials to the i.d.'s you created.”
Right… but in my opinion that doesn’t answers the question.
If you create a Multi/Sub Object material for you 3ds model, you can assign specific materials to the IDs after import to UE4… thats true… but how you can access the surface properties in UE4 so you can rotate, flip and scale the material(s) on your model?
The manipulation of materials needs to be done on via a Dynamic Material Instance (i.e. scaling, rotating, flipping, etc). All of this can be done through blueprints by selecting your Multi/Sub Object while placed in the level, and then adding it as a reference within blueprints.
You can then drag off of that reference and begin getting the specific materials assigned to that object.