The parallels Oda has put in Thriller Bark arc are insane. Could be reaching, but take it as you will in understanding the amazing foreshadowing Oda has put into Thriller Bark.
1st Parallel
-The situation with Absalom and Nami in the bath compared to the situation with Stealth Black Sanji in the bath house. And, of course, Sanji wanting to be invisible, got made into a reality in Wano.
2nd Parallel
Stitched up Pig holding 2 swords.
And as you may know, Pig God after he was cut by 2 swords from Oden, he had to be stitched up.
3rd Parallel
As you know, there’s a theory about some Rocks member being zombies.
And in Wano, we were introduced to Rocks Pirates.
4th Parallel
Foreshadowing of the Numbers in Wano.
On a side note, this could foreshadow the Zoan Army.
5th Parallel
Chopper commenting on Lola’s charging
Whitebeard commenting on Oden’s charging
6th Parallel
Foreshadowing Kiku?
Future Parrarels?
Could the Cerberus be hinting at Blackbeard coming to Wano with a Cerberus Devil Fruit?
Could it be referencing Kyoshiro as the guard dog to Orochi’s hell?
Could the Greatness of the Franky Docking play a part against Kaido?
Could Brook using his salt on the zombies, be the same as Tama using dango on SMILE users?
Maybe we potentially might get something similar to Nightmare Luffy?
Will the Battle against Kaido be similar to the Battle against Oars?
Could Ryuma play some role?
Will Franky and Robin team up?
Could Zoro have a similar moment like cutting Kuma? Cutting Kaido?
*Theory by LogicalGoal5