1. Luffy vs Blackbeard for obvious reasons.
2. Zoro vs Shiryu for obvious reasons.
3. Sanji vs Pizarro (after he held Nami captive akin to Vulcan holding Venus hostage in The Adventures of Baron Munchausen, rescuing her). Pizarro seems to be a prominent member and highlighted as different from the other prisoners because of his clothes; Sanji would fight an improved Pica the way Zoro would fight an improved Absalom; seemed prone to argue with Shiryu in a similar way to other pairs of villains fighting the two Wings; gets salty over the bounty thing just like Sanji; comes from North Blue and seems to have cybernetic enhancements.
4. Jinbe vs Vasco Shot. Potential fishman and martial artist of the drunken fist, possibly an alcohol-based fishman karate. Highlighted as brutal even among his Impel Down peers. Jinbe was also confirmed as the Straw Hat who best handles alcohol, weirdly above Zoro so maybe it will play a role. Vasco has been shown using fire, while Jinbe uses water.
5. Franky vs Sanjuan Wolf. Common theory, Franky will turn Sunny into a mecha and will fight Blackbeard's "battleship" with it. A potential fight based on air blasts, with both General Franky and Thousand Sunny using them as their strongest attack, and with Wolf potentially capable of using his fruit as a balloon man and attacking with air blows as a reference to both Munchausen's Gustavus (quite an ironic one, it'd be) and the Big Bad Wolf (certainly, Sanjuan Wolf is big and is bad).
6. Nami vs Catarina Devon. Catarina Devon has a cat them yet she's a dog and enjoys beheading beautiful women; and Nami is the woman form the crew who is highlighted as the most beautiful (since even her bounty poster comes from modelling). Illusions, tricking, etc. could fill a role during this battle, too.
7. Usopp vs Van Augur. Hopefully Usopp's observation plays an importante role here, and even more hopefully, Usopp's tricks end up guiding Augur's wraps into his traps.
8. Robin vs Jesus Burgess. She isn't winning but ultimately Kuzan appears to froze him. Kuzan isn't really a villain and Burgess was the first to warn Teach about him as he couldn't trust the former admiral: Burgess will be proven right, but it will be too late.
9. Brook vs Laffitte. Fits aesthetically and in terms of styles, plus the whole singing/hypnotizing.
10. Chopper vs Doc Q for obvious reasons.
I think I didn't miss anyone.