Question Apply textures via RGB mask I'm Shader Graph

Hello,
I wrote this simple shader in the built-in pipeline that takes an RGB texture mask to apply three different diffuse, metallic, smoothness and normal textures and applies them to each color. In this case it's a leather on the sleeves, scales on the body and metal buckles.

I have attached an image to show the shader.

I am trying to recreate this in shader graph, however I don't really understand how to do this and have been having trouble finding solutions.

If anyone can point me in the right direction to recreate this I would greatly appreciate it.