In terms of damaging Kaido:
Luffy > Killer > Law(assuming GN won't have any effects in the future)>Kid>Zoro(Did nothing)
In terms of how productivity:
BM: Damaged 4 out of 5 WG. Helped Kaido escape Zoro's attack
Luffy: Damaged Kaido several times, Saved Killer from being Kaido's snack. Tanked Kaido's attack.
Law: Helped Zoro save Luffy, Damaged Kaido via GN
Killer: Caused more damage to Kaido than anyone else bar Luffy
Zoro: Saved Luffy and scarred BM and Kaido.
Kid: Slammed Kaido
In terms of attack power:
Zoro (Literally scarred the most durable characters in the series)>Luffy>/= BM >Killer>Law >Kid
Overall, Kaido remains the most impressive. The guy is taking attacks on top of attacks and still going strong without showing any sings of slowing down. Has impressive speed even in Dragon form. Forcing Law to physically dodge the attack without giving him enough time to think about teleporting. Dodging Zoro's attack when he's just a few meters away from him. Being able to hit G4 Luffy when the guy has FS.