Hi,
Thank you for reply.
You are right, the White_Stone* was downloaded from FAB and Stone_Tiles_ was downloaded from Quixel.
However still content of the images were different.
Following screenshot (from photoshop) is displacement file for both downloads
As I mentioned before, still not sure how it will affect the materials defined in project, but so far it seems, if I want to change references to Fab, I will need to re-define materials (due to image file name changes)
Thanks again and have a nice weekend