The 3 great powers with the marines existing for at least decades and the yonko and shichibukai titles being a new thing to come to existence post Rogers death. With them definitely not being the same people back then than when luffy started adventuring
At the start of luffys:
The yonko = Whitebeard, Big mom, Kaido, and Shanks
Newgate and linlin were already big names in the generation before with kaido getting recognized more around the time of rogers death
Shanks only became a 1 of the yonko 6 years ago meaning that before him there had to be someone else
My guess being shiki seeing as he was one of the top pirates along with roger and whitebeard during. I know the end of chapter 0 doesn't seem to fit but oda can simply just change the outcome of it since strong world isn't canon. Like maybe his plan failed a year or 2 in and he just decided to go back to normal. Other than him idk who it could be
The admirals + fleet = Aokiji, Kizaru, and Akainu with sengoku as fleet
Sengoku was still an admiral 13 years ago during the law/doffy flashback
Borsalino was still a vice admiral 12 years ago during the Fisher tiger flashback and with him being the oldest out of the logia trio i dont think they were admirals either
Based on that we're only missing 1 admiral
With Kong being fleet admiral still and sengokus and zepher being admirals
The shichibukai = Mihawk, Crocodile, Doflamingo, Kuma, Moria, Hancock, and Jinbe
Im not gonna even try and guess any possible members before with how confusing the shichibukai timeline is
At the start of luffys:
The yonko = Whitebeard, Big mom, Kaido, and Shanks
Newgate and linlin were already big names in the generation before with kaido getting recognized more around the time of rogers death
Shanks only became a 1 of the yonko 6 years ago meaning that before him there had to be someone else
My guess being shiki seeing as he was one of the top pirates along with roger and whitebeard during. I know the end of chapter 0 doesn't seem to fit but oda can simply just change the outcome of it since strong world isn't canon. Like maybe his plan failed a year or 2 in and he just decided to go back to normal. Other than him idk who it could be
The admirals + fleet = Aokiji, Kizaru, and Akainu with sengoku as fleet
Sengoku was still an admiral 13 years ago during the law/doffy flashback
Borsalino was still a vice admiral 12 years ago during the Fisher tiger flashback and with him being the oldest out of the logia trio i dont think they were admirals either
Based on that we're only missing 1 admiral
With Kong being fleet admiral still and sengokus and zepher being admirals
The shichibukai = Mihawk, Crocodile, Doflamingo, Kuma, Moria, Hancock, and Jinbe
- Crocodile became in his mid 20s him being 46 now. So anywhere from 20-22 years ago assuming mid 20s is 24-26
- Jinbe 11 years ago
- Mingo became one between 13-10 years ago
- Hancock 13 years the latest during her first voyage depends how long it lasted
- Moria became one at least 10 years ago
- We don't really know when mihawk or kuma became warlords
Im not gonna even try and guess any possible members before with how confusing the shichibukai timeline is