@Deicide:
I never said Vegapunk was in Mary Geoise, only that the events in Mary Geoise would lead us to Vegapunk (through Bonney and Kuma). Different ar s and locations.
What will lead the SH crew to Mary Geoise is Sabo/Vivi/Hancock. There they’ll get tangled with Bonney and the Revolutionaries. We’d probably be fighting CP0 and get our first showing of the SSG, and everything leads us to Vegapunk.
What would lead the crew to Vegapunk otherwise? Would they just stumble upon the location?
For the same reasons you personally expect the Strawhats to head halfway back around the world to Mariejois, I expect them to just push forward towards Vegapunk at an unspecified location. IMHO, I don't expect a trip to Mariejois until after they've sailed around the world and found Laugh Tale. To go backwards to FI, then forwards again past Wano doesn't make sense to me.
IMO, I don't think Sabo, Vivi or Hancock are captured, or at least not all 3 of them. I think someone like Bonney or Sabo will be involved with Luffy again to either sabotage the SSG weapons or rescue Kuma. Clearly there is some background there for Bonney, and knowing how Oda has involved a Supernova literally every arc since Punk Hazard, I wouldn't put it behind him to incorporate this as a plotline geographically after Wano. There are already a ton of ingredients for a Vegapunk arc that doesn't have to include Vivi or Hancock:
- Vegapunk himself, his SSG and weapons
- Kuma and Bonney, their relationship
- Sabo and his RA commanders, assuming they are MIA, but trying to still rescue Kuma.
- Smoker and Tashigi, whose last known locations were with Vegapunk. Fujitora did not return with them.
- Caesar and Germa 66 are both MIA. Both Caesar and Judge have history with Vegapunk. Chances are they will return during this plotline.
At this point, to assume yet another rescue arc for Vivi/Sabo/Hancock at Mariejois seems pretty simplistic, especially when they are all super far away from Mariejois at this point and need to keep pushing forward (for Oda's sake tbh). For example, I don't think Koby will catch Hanock. In fact, I can see them teaming up due to their personal infatuations with Luffy, and considering he's a Sword member and they seem to do unorthodox stuff to achieve justice. Vivi met both Sai and Leo at Mariejois, who both have Vivre cards to Luffy. Yes, I see her father dying from the events that occurred, but I don't think Vivi was captured, rather one of these 2 rescued her and escaped.
Just 2 examples of other possibilities. I don't think any of them were captured in the traditional sense, if I'm being honest.
Edit: You also have to assume, in your case, that each one of those characters (Sabo, Bonney, Kuma, Vivi and Hancock) are at all at Mariejois still. Its been a week since the Reverie and who knows how long in the story until Wano officially ends.
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Hell, a Vegapunk arc could also involve Hancock and Vivi. It could involve CP-0 and the Tenryuubito. It could involve a ton of factors like Crocodile, the Underworld, Blackbeard or Shanks, etc.
But I really don't think Oda would take the crew halfway back across the world yet when they are so close the end of the actual adventure. To me that just doesn't make narrative sense to ruin that. This is why I believe that Vegapunk's facility is a post-Wano location, and Oda will somehow tie Luffy into this.
Sabo has Luffy's vivre card, he could arrive at Luffy's location with Karasu at any point he wants to and involve him in the plot. Bonney could just be a chance encounter at the next island. Its things like this we have to consider.