Painting sloped cliffs/angles?

Does the Blender texture painter offer painting stuff on certain slopes/angles? For example you want everything that is flat to be grass/sand and you want something that is steep to be a rock texture, so can that be done in Blender or do I need to use Substance painter or something?

I think that I’ve seen once something about some program or addon doing this automatically for the whole terrain, but I am talking only about manual painting, like how you’d pay in most game engines and map editors.

How does that work exactly, does it prevent you from painting on certain slopes and allow you on more flatter/steeper ones or what?

Also, where do I even put that in relation to my current alpha texture node setup?

That’s a mask based on slope. It won’t prevent you from painting anywhere, you have to connect it to the ‘Fac’ socket of your Mix Shader.