I do treat patients with fat grafting and fractional laser resurfacing using Starlux2940 at the same time.
I typically do this procedure on the eyelid as part of an arcus marginalis release and fat grafting to correct dark circles under the eye.
The fat will be injected deep into the lip beneath the skin. The Fraxel will be affecting the skin surface down to 300-500 microns and will not go below the skin surface, where the fat will be placed.
I would do the fat transefer first, because once the Fraxel has been done, I would not want to then pass a needle through the resurfaced skin.