Admirals in general? Not past Yonko level, that is for sure although any of them can give any Yonko a high diff fight. I am of the mind that, if any admiral >>> any Yonko, the Yonko would have been dead a long time ago.
Though, I must say that my list was made with Luffy = Zoro aka World's Strongest Duo dynamic in mind (as in, Luffy is captain of SH because he is the only guy Zoro would follow, so naturally, if Zoro were to become an admiral, the only one whose orders he would follow as a Fleet Admiral would be Luffy's).
Imo: Post Wano World's Strongest Duo > Any sole living top tier.