This will only work for C++. To use GameplayTags you will need to load them at editor start, and to do that, you will need custom Engine/EditorEngine classes.
Coding them is fairly easy:
As for componenets. I don’t mean an componenet added in componenets panel ;). I mean just very simple class which contain data, about what it is, and with what it can interact.
The general idea, is that you add crafting objects into single array, and then check if they match required composition to actually craft (spawn) another object.