On the surface, it makes narrative sense for The Book of Boba Fett to showcase several bounty hunters, but the report mentioning the term “fan-favorite” means that characters viewers already know will make their much-awaited return (or debut) in live-action.
Cad Bane is the clear front-runner to arrive in The Book of Boba Fett, considering the character’s connection to the titular bounty hunter.
LRM Online shared in a report that The Book of Boba Fett will feature “some fan-favorite Bounty Hunters.” Beyond that, details about which bounty hunters will appear weren’t outlined
It was made clear during Star Wars: The Clone Wars that Cad Bane was the one responsible for the dent in Boba Fett’s helmet. By connecting the dots, it’s reasonable to assume that Fett will likely pursue Cad Bane for that “unfinished business,” leading to an eventual confrontation between the two characters