- Titles are all rumors, no one cares about that thing.
Zoro Novel: ''One marine claims that the strongest swordsman in the world is definitely Mihawk, the other marine claims it's Zoro. They witnessed their sword techniques in marineford and dressrosa. Mihawk cut down gigantic ice block. Zoro cut down gigantic Pica. They start talking about other candidates: Vista, Shanks and Ryuuma. A marine says Vista was able to fight Mihawk equally for a short moment. Ryuma is strong, but he is already dead. According to another marine, Shanks is said to be the rival of Mihawk. He faced Akainu without fear. 2 of the marines have heard that Shanks is a very strong swordsman. But another marine says it's not that Shanks showed his great technique with his sword in Marineford.''
--- Translation by Sandman
So he doesn't stand anywhere above.
Vista had a competitive fight with Mihawk, which ended in a draw.
"Vista has the skills to compete with Mihawk, one of the most famous swordsmen in the world. He wasn't afraid to confront him..."
--- Vivre Card - One Piece Visual Dictionary
- Shanks and Mihawk are not rivals, and making up an excuse for an arm is hilarious as we know people like Queen and Nekomamushi lost their arms but replaced it with weapons, Shanks doesn't even do that because he is above of that level, he doesn't even need that. Mihawk will soon join Red-hair pirates, he already declined to fight with Shanks twice before despite being a Shichibukai, enemy of the Yonko. But he was like Jinbe to Whitbeard pirates, he is friendly to them. And now he lost his castle and forced to run, he will definitely need someone to join, he can't run forever alone.
- Whitebeard knows almost everything, he also remembers even Buggy, that doesn't mean anything.
- Oda groups Whitebeard and Shanks together as well, that doesn't stop you from saying Whitebeard > Shanks. It shouldn't stop you from saying Shanks > Mihawk. Ridiculous arguments.