neither

Losing to Mihawk is still currently a bit less bad than losing to Sanji
Tbh, I would prefer Wings vs Admirals because those fights would be more fleshed out, and Fuji/Ryo are very Zoro/Sanji coded opponents, but I really do think that at this point, it would just be cleaner for the story if Oda just has Akainu and the Admirals each go after a Yonko post-Elbaf and lose before the Yonko battle royale in Lodestar. Lodestar will already be cramped enough if Oda follows through with having all the Yonko battle over the 4th RP there, and adding in all the Admirals and other Marines would just make that problem even worse.

I always found it kinda odd that Oda never had Luffy visit Sphinx, where Ace’s grave is located. So maybe the crew stops by there after Elbaf and fight’s Akainu’s fleet there? Or I guess Oda could just have Luffy visit Sphinx in the epilogue.

The biggest problem with my theory is that I genuinely can’t even imagine Oda actually letting Mihawk beat a prominent character prior to his fight with Zoro (assuming Mihawk doesn’t die to Shiryu or something)
 
No one should want their fave to face off against the godking, in all honesty. Their stocks would drop so bad.
Fatbeard fans are somewhat immunized, since they're used to their goat looking like a jobber in nearly every fight.
Tbh with Greenbull it's kinda different as the current running narrative is that he went down without a fight by getting paralysed from thousands of miles away.

So him actually holding his own against Shanks in any capacity would make a lot of people big mad.

Same goes for Kizaru/Fuji to a lesser extent thanks to film Red.
 
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