Marco, Sanji, Yamato, Jinbe ... All of them were prevented by plots forced to not reach the roof, so that Oda could give a special panel to the supernovae, especially Luffy / Kid / Law that has been provoked since sabaody .
Marco is not going to fight a calamity, he is obviously stronger individually than King / Queen, and a MarcoVSKing individual fight would be anti-climactic, Oda does not design fights because they will be aesthetically pleasing to please those who like well-designed fights, he never did that. And Marco is not dimming the brilliance of the mugiwaras in being the stars who will defeat the Beast pirates, so he's not taking down someone important down in the grand scheme of things
Marco is participating in the fight in the roof, against Big Mom, the reason he is not there yet is because Oda wanted to give a special supernova panel, Marco will probably make an important sacrifice, protecting the ''new age'' and Oda has yet to work on the phoenix resurrection thing, which is something Oda is likely to bring to the manga, and that will only be possible in a scenario where he fights against yonko
Sanji and Jinbe have already shown interest in going up to the roof and Sanji in particular said indirectly that he will participate in the fight to ''take down their commander''
But for plot reasons, Oda also prevented them from getting there for the supernovae to get their special panel.
Yamato is another who has shown interest in fighting Kaido by rebelling against his father who has kept him imprisoned all his life. And by plot he is also away from the dome protecting Momonosuke. Obviously we will have a Yamato vs Kaido panel
Those 4, King and Queen will inevitably climb to the roof at some point, and it is there that they will have individual clashes, especially ZSJ vs KQJ
If Sanji beats Queen solidly, I already put him at the Jozu level.
I have Marco/Jozu above the King/Queen, and I have post Wano Zoro / Sanji having a dynamic similar to MF Marco/Jozu (the last 2 were balanced with the baseAdmiral in MF