I’m betting this arc will have many parallels to Thriller Bark, I’ll list all of them here, so let me know what you think in the comments below!
Vegapunk could steal Luffy and make a robot/seraphim of him, but it disobeys him because Luffy has that innate desire to be free -this will also essentially be Moriah’s zombies with shadows, but this time it’s Robots or Seraphim with fruits or souls, opening up and answering the question of what a soul is, what a devil fruit is, and if a robot can even have a soul or devil fruit.
Potentially all the Strawhats have to beat Robot-Luffy, Franky decides to bring out a new version of Tactics-15, and Robin joins in this time. This could be a wild Oars parallel!
Franky sees all the creations Dr. Vegapunk has made, and likes them at first, but upon seeing how they’re used (tying back to what Tom told him), he begins to hate Dr. Vegapunk, just like Chopper hated what Hogback had done.
A derivative of Germa Tech will serve as the Absalom Invisibility thing.
This arc will also tie into the real world idea of scientists taking things too far, and things happening because of them creating unnatural phenomenon. This is because Egghead, although a Winter island, has a tropical jungle in the middle, implying that he finally finished building his island heating apparatus, and it changed the island’s season type to irreversible affect on the environment (like global warming). Also will be exemplified in the robots who are given sentience, and turning against their creator.
Finally, this arc will serve to prove that Luffy is indeed a God, he can’t be recreated nor controlled. No matter how you try to cage the Nika fruit, it will find a way to be free.
Theory by WindyFromWater7 (https://www.reddit.com/user/WindyFromWater7)