How do you think Buggy become Yonko over Mihawk? WB hyped Buggy's crew and they are stronger than Mihawk, and Mihawk is not Yonko level.
I'll spell it out for you so you can understand cause you keep thinking you are Oda and know everything...
We don't know how Buggy became Yonko over Mihawk, that's yet to be explained exactly but you can't even wait for that and already spewing lies.
The WG might think Mihawk is working under Buggy as we've seen in this chapter which Zoro himself tells you not to believe but you'll do that anyway cause why not right? Just one likely possibility.
And Mihawk being the WSS means he over Yonkos like Shanks (let alone someone like Buggy who ruined the Yonko name anyways). You can cry about it all you fucking want, that will remain a fact and it's not gonna change. It's not some BS like "Law mentionned Mihawk and Croc in same sentence" that means they are equal lmfao.