My headcannon about the SHvsBBP matchups has always been
BlackBeard vs Luffy
Shiryu vs Zoro
Laffitte vs Sanji
Van Auger vs Usopp
Burgess vs Franky
Jinbei vs San Juan Wolf or Chopper vs San Juan Wolf
Nami vs Caterina Devon
Chopper vs Doc Q or Brook vs Doc Q
Pizarro vs Brook
Robin vs Vasco shot
I was always
Burgess vs Sanji (the masked fighters)
Shiryu vs Zoro (the swordsman)
Van Augur vs Usopp (the snipers)
Pizarro vs Jinbe (this one just feels right idk why)
Lafitte vs Brook (the angel vs the soul king plus both fight with canes)
Catarina Devon vs Robin (also just feels right)
San Juan Wolf vs Franky (colassol battleship vs Battle Franky plus I feel like general franky is going to get an upgrade to be even bigger than it currently is so we get giant battle)
Vasco Shot vs Nami (Let the heaviest drinkers fight)
Doc Q vs Chopper (Doctors going at it)