It's very likely to be a more chaotic match up then 2 vs 1, like there were not only Garp, Roger & Rocks against Imu, but also there were BM, WB, Kaido...who didn't last long ofc, and this is something I expected to be paralleled as well.
But then it gets a little complicated.
Do we get a marine and a pirate? Then Coby + Luffy, but both of them are throwing punches.
Do we get a swordsman and a fist fighter? Then it's Luffy + Zoro or Luffy + Law.
Do we get 2 enemies against the common evil? Then it's Luffy + BB (and you could also argue for Luffy + Law as they're rivals).
Personally, I expect all SHP with haki to be involved somehow, even for a clash, and Luffy + BB + Koby to be on the central stage as descendants/spiritual successors of the old gen.