The Joker will recruit or "create" two others to create the Three Jokers.
After Sanji disfigured the Joker, he's physically no longer able to smile or laugh. Driven even further to madness for this, he'll try and find a way to restore the legacy of the Joker even if he can't do it completely anymore. Through whatever methods he finds, he'll turn two other men into fellow Jokers to work with and bring his name back. Fittingly, the original Joker will be the Criminal among the Clown and the Comedian. Doomsday will be reprogrammed to have a hateful obsession against the Straw Hats instead of Superman.
- Already Waller and the U.S Government is beginning to see the Straw Hats as a bigger problem than the Justice League. From raiding their secret military base and taking the Royal Flush Gang to learning of the dark alternate reality where the majority of the Straw Hats driven mad from grief were winning in destroying Vandal Savage and his regime; will begin taking actions to apprehend or eliminate them. With the events of Maid of Honor likely to be the final nail to solidify this as they reutilize Doomsday as a weapon against the Straw Hats when he makes his appearance in "A Better World".
Amazo will eventually be able to replicate devil fruit powers once he realizes and understands what his "dream" is.
- While so far it’s confirmed he cannot replicate devil fruit powers yet, it is likely when Amazo learns more about life and what his dream is that this flaw will be overcome. Since Vegapunk clarified Devil Fruits are the embodiment of humanity’s collective dreams made reality, thus when Amazo finds out what his is will be able to achieve copying devil fruit powers like he can with haki.
Chopper could discover Brainiac’s nanites when examining Lex Luthor.
- It’s quite evident at some point those two are going to meet, given Lex knows quite well that Chopper could cure his kryptonite cancer. Especially since Chopper and Cheetah are actually working to cure it themselves. Thus how or when this plays out, will lead to Chopper discovering Brainiacs nanomachines festering inside him.
Farmer Brown and Emmylou will go to the Grand Line with the Straw Hats but simply stay in Wano.
- Luffy has stated his intentions to bring the plentiful food and genetically modified livestock Farmer Brown and his daughter are making to the Land of Wano once they find a way back home due to wanting to keep his promise to Tama and feed her and the starving people of the country. Thus it is likely that they not only help feed the starving nation, but Farmer Brown and Emmylou will stay in the Grand Line and live in Wano given how it’s denizens will appreciate their work far more than Earth did.
Who could go with the Strawhats back to their world.
- Cheetah may seek to regain her humanity with Chopper’s help and be a normal person again, but she does have some potential to go with the Straw Hats from her time with Chopper and learning her presence wouldn’t be too odd in the Grand Line. Especially when she learns of the Mink Tribe when or if the topic is brought up, that being a tribe consisting of countless humanoid animals just like her. Needless to say, that alone may help her overcome her insecurities over her appearance and make her decide to make a new life in the Grand Line.
- Harley Quinn both to get away from Joker once having finally overcome all of her trauma and severed all ties to the frowning clown and to have more fun with her new friends and go on all sorts of wild adventures.
- Poison Ivy is also likely to come if Harley goes to the Grand Line due to their friendship and the fact she wouldn’t pass up the chance to repopulate the Land Of Wano with vibrant flora and vegetation nor punish the Beast Pirates for defiling the beautiful flora with their factories pollution.
