This is the carbon approach I've used for years now:
The dual MK in this inkset is only for Arches watercolor paper, which, frankly, I have not used in a long time.??
That said, the image on my wall? --? ? --? ?is a100% carbon, neutral-appearing print on Arches that will outlive us by multiples.? (But who, other than museums, really cares.)
PK, MK, and dilutions of PK will do satin (what I prefer), glossy and matte papers.? ?
I do use a bluish "toner" that is a blend of Canon blue and cyan inks to?offset the yellowish tone of carbon.? I think it is the most stable we can mix from commonly available pigments that are compatible with Epson inkjet printers.?