That tool, my friends is Materialize by Bounding Box Software!
https://boundingboxsoftware.com/materialize/
You can basically take a diffuse/colour texture and materialize will generate all the maps you need for PBR! Pretty neat.Materialize is a stand alone tool for creating materials for use in games from images. You can create an entire material from a single image or import the textures you have and generate the textures you need.
I am going to do more of an in-depth guide to the tool on my blog soon, as I want to provide a few tutorials on quick and easy ways people can remix the textures provided in some of my upcoming products and this would be one of the ways I recommend making materials if you only have access to the original colormap.
The UI is a little unintuitive in places, but overall its pretty straightforward. There are lots of parameters you can play with. Its not suitable for ALL applications (especially if you are relying on the application to generate the heightmap for you) but its a great free way for people to begin playing around with PBR.
Obviously, getting these maps (especially the heightmap/normals) from an original sculpt is almost always a superior option. But it does a pretty good job from just a 2D image, and in many cases will be a decent option for quickly updating older content where the original high-poly sculpts are no longer available or accessible, or only a 2D image ever existed in the first place.