In chapter 909 the name of the Shogun of Wano Country is revealed to be Kurozumi Orochi.
According to Japanese mythology Yamata no Orochi (“8-branched giant snake”) or Orochi is a legendary 8-headed and 8-tailed Japanese dragon.
Susanoo, the Shinto god of the sea and storms, killed the Yamata no Orochi.
We know Zoro uses a tornado attack which connects to storm so he will defeat/kill the Shogun.
Furthermore Oda and the author of Naruto are friends and Oda had done shoutouts to Naruto before with Raizo. Zoro will likely defeat the Shogun Orochi with the Asura technique or an upgraded version of the Asura as a result of the training and I felt that Asura technique was a bit of a reference to the Susanoo from Naruto.
Also the Shogun Orochi could very well use 8 swords as a reference to how Killer Bee from Naruto used 8 swords plus there is the fact that in the Yamata no Orochi Myth after expulsion from Heaven, Susanoo encounters two “Earthly Deities” near the head of the Hi River, now called the Hii River, in Izumo Province. They are weeping because they were forced to give the Orochi one of their daughters every year for seven years, and now they must sacrifice their eighth, Kushi-inada-hime so this will be referenced with the Shogun taking the other samurais swords so along with his main sword which will be a reference to The legendary sword Kusanagi-no-Tsurugi, which came from the tail of Yamata no Orochi.
The Shogun will have 7 other swords he got from defeating other samurai meaning that he uses a total of 8 swords since the Yamata no Orochi had only gotten 7 of the daughters in the myth so replace the daughters with swords and the 8th daughter Kushi-inada-hime will be represented by Shisui the national treasure of Wano which Orochi would want.
So, after defeating him, Zoro could get a new sword in Orochi’s main sword which will reference The Legendary Sword Kusanagi-no-Tsurugi, which came from the tail of Yamata no Orochi and how Susanoo had obtained it from the Yamata no Orochi’s body (though Susanoo in the myths had given it to Amaterasu to settle an old grievance) they could change it so Zoro keeps the blade along with Shusui and Sandai Kitetsu breaks or he can give Kusanagi away or he can return Shusui.
*Theory by darkstrike
