I noticed that it seems like the islands that the Straw Hats were sent to for 2 years are foreshadowing the locations that the Straw Hats are going to.
If you compare the island that Sanji was sent to and Whole Cake Island they are very similar, both look similar and have an importance with food. So we have Sanji’s arc.
We could also compare Kuraigana Island and Wano, both islands have primates that are skilled in swordsmanship. So we have Zoro’s arc.
I think that Elbaf will be the Usopp arc and it will be like Boin Archipelago.
If we follow this line of thought we can try to predict other islands that Oda might make in the future. I personally think that Raftel will mirror Rusukaina, both being destroyed civilizations and possibly both having 48 seasons (this is also assuming that the Raftel arc will be the Luffy arc as Whole Cake Island was Sanji’s arc).
So this leads me to believe that in the New World we will see another sky island(Nami’s arc), a primitive island with a undiscovered medicine(Chopper’s arc), future winter island(Franky’s arc).
This only leaves Nico Robin and Brook, and that’s because they both ended up traveling during the time skip (Robin with the Revolutionaries, Brook with Sancrin the Thief). So I believe that rather than a single island these two will have groups that define their arcs (Robin with the Revolutionary Army and Brook with Laboon and Crocus).
*Theory by DuckyKuhn
