Aokiji can ambush solo Kaidou and Blackbeard crews without their captains

[Warmmedown]

He froze Blackbeard's entire crew, except for Blackbeard himself. He could do the same to Kaidou's crew since King, Queen and Jack don't have conqueror's.

Katakuri in Big Mom's crew causes an issue, but he can turn it into a 1 vs 1.
Mihawk and Crocodile are an issue in Cross Guild. If Mihawk was counted as captain then they're screwed.
Shanks' crew probably has a couple of strong conqueror's users. Maybe they have some chance.
Luffy's crew has Zoro and probably Sanji will have conqueror's or breaks out of the ice somehow with the power of limerence.
Whitebeard's crew just has Ace's fire powers.

 

[Warmmedown]

Even without an ambush, he needs to avoid getting hurt too much and just touch them all like one time to freeze them. If it's an area without potential collateral damage, he just freezes them all. He's insanely powerful if you don't have conqueror's. More formidable against multiple non-conqueror's enemies than Luffy or any other admiral.