Male GOAT: Conor McGregor.
Female GOAT: Ronda Rousey.
You cannot be GOAT if you haven't been in the UFC, sold more than 1 million PPVs as a headliner, landed on the cover of SI and won at least one ESPY award, that is all.
Saying Fedor as the GOAT is laughable. Look at the GOATs in other sports: boxing GOAT Ali -> most famous athlete like, ever. B-ball GOAT Jordan - billion dollar blockbuster draw. Being the biggest blockbuster draw is a pre-req for GOAT status. Fedor has never competed in the premier org in MMA, nor was he remotely close to the biggest star in the sport. He's no GOAT.