Saying that Luffy can beat them all, really? If he fought Hancock here Luffy will surely lose here, after all Hancock was more powerfull than the Sentomaru(Kizaru's nephew) that Luffy can't beat on Shabody.
If you had a brain sure Hancock is strong bc everyone thinks shes beautiful and if they have that thought it stays there because of her charm they all fall for her but Hancock couldn't turn him into stone, and CANT turn him into stone. Why? because he isnt charmed by her beauty.