as for that Baratie scene, Usopp may not have known Mihawk (for whatever reason, which is dumb because he SHOULD considering he knows Shanks who went on “”””legendary””””” duels with him lol), but he still got wanked by Zeff and Zoro nonetheless.
What is surprising is that Luffy didn't know even though he spent his days hanging out with Shanks and his boyband, they never mentioned the swordsman has regular legendary duels with Shanks.