I have 2 normal and 1 premium Alba Armored Cavalry and 1400 Meteorite Powder, yet I only can create a new premium copy through crafting with scraps and powder, it does not give me the option to transmutate when I "zoom in" the normal version. Other cards where I have the same combination of normal/premium I can transmutate.
From what I understand there is no way you can get rid of base set non-premiums, the premium versions can get milled, however not the non-premiums.
It appears CDPR does not want us to not have those available, from which I gather that you cannot transmute them either.
Edit: I just checked this in the game, it is indeed a base set card and as such the non-premiums cannot be disposed of.
It appears CDPR does not want us to not have those available, from which I gather that you cannot transmute them either.
Edit: I just checked this in the game, it is indeed a base set card and as such the non-premiums cannot be disposed of.