The black cat we adopted recently started off as Isabel, until the vet confirmed different parts
. By then, regardless of gender, he was already Izzy and Izzy he remains.
Blackie would be an obvious, if lazy, name for him but we've already had the late, great Blackie (who was mostly white). Blackie I passed on just over a year ago, so too soon to recycle a name.
The other cat is officially Gracie, but that has somehow morphed into Kitsie.
My brother had the gift of great cat names. He once had a pair of orange tabbies named Toccata and Fugue (as in D minor). When they had a litter of three kittens, they became Johann, Sebastian, and Bach