Zoro : Wait! Wait ! Don't eat ...
Zoro : My captain!!
Zoro : Santoryu!
Kaido : hm ??
Kaido : This form of haki!!
Zoro : Kujou Ô Tatsumaki!!
Kaido : Uoooo!
Killer : (sorry the picture is cut)
Big Mom : That kid .. He managed to cut Kaido
Kaido : Oh .. i see it's working! That's Oden katana ?
Kaido : To think you challenged me with Tatsumaki, Uerororo"
We talk with
@ivaannom so before claiming lots of things, we agree that 正体 means form or identity.
So Kaido is seeing here that Zoro is using the same haki of Oden "Ryou", exactly like when the scabbards used Ryou on him. For Kaido who doesn't know anything about Ryou, he refers Ryou to Oden's haki. That's when Scabbard and Zoro used on him, he calls/sees that at Oden's haki. Also why he didn't understand how Luffy hurt him with Red Roc at first.
No there is no haki of Oden here.
Correction to the slightly off mis translation from the previous post to this portion.
"Zoro : That's actually not a simple tornado!"
Zoro actually states. "That's (that referring to kaido) just a disaster!"
It is easy to mistranslate this as it uses ただ which directly translates to simple or just.
As for the Oden's Haki, Kaido saying Odens Haki does not exactly mean he has the same Haki, but more the same level of haki, as Zoro is starting to adapt to the sword that only Oden was able to wield.
Well guys, there you have Zoro is a monster in term of hacky, a clear genius one in 1milion or more able to understand Enma, that in 20 year or more none in Wano was able to use it.
Zoro is like Luffy (Joy Boy).
A prodigy that ll safe Wano