I think all the Supernovas are gonna be at Wano just like Sabaody.
I believe 9 of them are already somehow directly involved with/near something Kaido-related.
1.Luffy-Law alliance against Kaido/Shogun, which includes Zoro.
2.Eustass Kid is currently imprisoned by the Yonko himself.
3.X Drake and Scratchmen Apoo are currently “working” for Kaido (although I believe it’s only for now until they make their move).
4.Basil Hawkins & Killer are either imprisoned by Kaido or are allied with Kaido or are laying low for now, waiting to make their move.
5.Urouge was at Balloon Terminal near where Kaido wrecked the Kid-Hawkins-Apoo alliance.
That’s 9 accounted for.
Only Bonney and Capone seem to have no clear ties to the conflict. BUT Bonney was shown to be in a winter island like Wano is suspected to be and Capone might end up tagging along to Wano having nowhere else to go.
*Theory by viktorayy