Having finished my first course, I delved a bit further into UE4 materials before beginning the second course which will take months to complete, most probably.

UE4 is incredibly powerful when it comes to materials. Or shaders, I don’t quite see any difference between the two.
Either way, it’s very easy – so to speak – to apply PBR – physically based rendering – materials onto objects which can change at runtime : change the color of grapes from green to purple along the maturation, or apply a wet shader to all materials in a level after rain.

It will take me around two weeks to gather all the necessary information about materials, I’m now following official Epic courses which are of very high quality.