I know nothing of an add-in for this, but at SWW they previewed a new feature for SW 2019 that would add texture to the 3D model based of an image/decal. - so maybe try out the 2019 BETA.
If budget is no object 3-matic Modules | Materialise 3D Printing Software
Otherwise, you might be able to export your models as meshes and do it in Blender or similar. Getting the right topology and displacement mapping will be a learning curve though.
In the unlikely event that your surfaces are planar only, there's a cool SolidWorks add in here Image2SOLIDWORKS