I'm convinced Koby can see the future. Each time Oda brings back an old character, they are noticeably stronger.
It makes no sense for Koby to merely have good CoO, because he already had that pre-skip by the end of marineford.
if Kid, Law, and Lucci get awakening, Koby should have FS.
It also makes perfect sense why he was the only one who didn't get petrified in amazon lily, when even his superior officer and the blackbeard commanders were turned to stone. He was the only one with FS.