Thanks for your answer. Digging more on the topic what I'm searching for is procedural texturing, manageable from external scripts. In my research I find only a couple of software able to doing so, all of them node based, so I suppose no luck with Megascans materials.
For my project need to be able to change by scripting the materials properties. Looking at Megascans as potential source for base materials I can use to derivate a new set, want to know where I'm starting from, so if there is any documentation about the base value used to create these materials. Since Mixer it's not…