I’ve found a better explaination about setting up blender material with both roughness and metallic textures
and
TLTR you can bake these textures in a single texture using the right channel (it’s even a performance improvement so you may want to check it)
note that unity uses smoothness that’s the opposite of roughness, but it’s everything well explained in these forums posts
maybe this is something @Rick_Davidson could be interested into to extend current lesson