How to link Mapping Node to all textures at once (without add-on).
Use Node Wranglerarrow-up-right add-on to speed up work on your shader.
Once all the textures for the MultiTexture are in the Shader Editor and you want to link Mapping Node to them - do this:
Select all textures
Holding Shift select Mapping Node
Shift
Press Karrow-up-right