Mihawk is the physical manifestation of his sword Yoru looking for someone who is worthy enough to wield him (theory) : r/OnePiece

Roronoa Zoro/Abilities and Powers, One Piece Wiki

Destiny's Foil (One Piece Semi-SI Gamer)

Who are the most powerful swordsmen of One Piece? - Quora

Characters who could potentially possess or awaken conquerors haki

Someone's Haki : r/OnePiece

My reasoning as to why I believe Mihawk > Shanks : r/OnePiece

Mihawk is the physical manifestation of his sword Yoru looking for

Early example of Zoro's Haki? : r/OnePiece

Is Shanks (still) a Swordsman? : r/OnePiece

How good is Mihawk in sword skills in One Piece? - Quora