By the look of it they paint it with dye. That would be hard to re-do. But adding layers of cream and polish would certainly change the effect, although on cordovan, the general advice is that less is more. I'm not sure you want to try to change the look of a cordovan shoe too much.
I am not looking to change the color of the shoe. More just to keep the color it started out with.
I was thinking that this
would likely be good enough for maintenance level recoloring. But Ive never owned shell and even less meermin's argentinian shell.
Since if the color is painted of after the tannery it will get lighter with time because it will not get into all the pores of the leather