There is Bigmom vs Kidd and Law, Apoo vs Drake, Killer vs Hawkins and the most legendary fight Raizou vs Fuku or whatever. I bet any fight can be off paneled but Raizou vs Fuku is what we unfortunately get full focus. So until these things are clear, we won't even see the glimpse of Luffy vs Kaidou. Even if we see, it is just glaring contest between Lufty and Kaidou. But Oda is an ass if he doesn't give some focused to Law and Kidd vs Bigmom in the next chapter.