This is the merch I want most, and it seems so easy, and so intentional, that I cannot believe a deck like this isn't already on sale.
I found a reddit comment suggesting that they were commissioned by a Polish artist by the name of Jakub Rebelka, and there's an artstation page under that name with very similar style art.
I almost punched all the files into a custom game card design website, but I don't have the rights, so obviously I didn't go through with it.
If CDPR would sell these as a deck, I would own them as soon as I could get them. If Jakub Rebelka sold them, I would purchase a deck without hesitation.
SOMEONE PLEASE MAKE THEM!