I think there will be many different battles, since this is a war, not a group of 6 infiltrating and getting confronted by 7 very strong people they had to surpass and beat. There is Law, Kidd, wildcards like Drake, Hawkins, Apoo, the retainers, minks, samurai etc., vs not one, but 2 yonko.
I think it would be more like Marineford. All 3 admirals attacked Whitebeard at some point, Marco attacked every admiral, Crocodile attacked everyone, Hancock attacked everyone who touched Luffy and so on. It looks like the forces are splitting up (and atleast one additional is probably on their way) so we might see lots of different clashes, but in the end it will be Sanji finishing Queen and Zoro finishing King. Still not sure about Jack, leaning towards Jimbei. Odens retainers will for sure go for Kaido, but it will be the supernova that ultimately defeat him