Are we going by skill or overall strength? If skill, Zoro should most def be up on the list. Roger shouldn't even be on the list in terms of skill being real and the same goes for Big Mom. They're swordsmen, but they aren't skilled swordsmen.
You’re really putting Mihawk below Shanks in a ranking of if they are good swordsmen or not?? Mihawk is the world’s strongest swordsman so he is clearly a better swordsman than Shanks. I already disagree when people say Shanks > Mihawk overall, but saying Shanks > Mihawk judging on swordsmanship only is objectively incorrect!!
By that logic, Mihawk is not only the strongest swordsman, he’s also the strongest overall. Which I agree with, but I don’t think that’s what you meant.