here is how infamous 3 can happen. kessler travels back in time to prepare cole to fight the beast, this tells us that someone from either future could posses the ability of time travel, allowing them to go back in time with a charged rfi give it to seek to activate after he/she brings cole,nix, and kuo into the near future after the beast and plague have been destroyed.
It would make sense for Infamous 3 almost like Prototype 2 It would take place after the evil ending and he activates you/main character and kills your family or something so you begin to get powers like all the Infamous games and there on it would be really good like the world is in an Armageddon state and your a hero that rises out of the ashes and you fight Cole and the Evil conduits gaining supporters throughout the game to help you defeat them.
Some thing that might be possible, if a bit sci-fi for inFAMOUS 3 to work.
It is set 10 years after inFAMOUS 2 and the story of the conduits has become a touchy matter with some linking to religious signs to others claiming that governments are hiding possible super human abilities from the populous and that the higher class are receiving these abilities. Zeke, the human who is the person who understands the situation best was kidnapped at sea along with the body of Cole. He was kidnapped by the heads of Vermak 88 and was questioned and even tested on due to his certain "exposures." Eventually Vermak 88 have the technology to go fourth with their plan. They create something that can do a one way time travel and a single merc, using technology available at that time to not cause to much public speculation, guns down Cole in the street, disposes of his body and kills himself. In the alternate timeline only Vermak 88 and the first sons know about conduits. As for the beast, Kessler sacrificed his life to stop the beast from leaving the island of empire city. You, the protagonist are kidnapped by Vermak 88 as you have the conduit gene. Vermak 88 are able to used controlled ray sphere energy to activate your powers (just as a bonus feature I really wanna see implemented you are somehow able to choose them.) After the situation is explained to you and you test out your powers there is a surprise attack on the building by the first sons. The more powerfully conduits fight but you hear that the first sons basically are now trying to use their powers to protect mankind while Vermak 88 use their powers only for money and self betterment. A normal human tells you to follow him and you take cover in a bunker where Vermak 88 were able to preserve somethings from the changing timeline including themselves with their knowledge and Coles body. A strange energy emits from the tomb and connects with you. There is a burst of power from you that destroys the building and only you survive. You then chose whether to side with the first sons or Vermak 88 and then the events of inFAMOUS 3 unwind. It is revealed later on that the energy from Coles tomb was some of his power that you were able to absorb as it turn out that you have the same potential he had and you are the only thing now that can destroy the beast once and for all.
What do you think? Something like that? I dunno, I don't really care just don't be mean to me due to my stupidity. All I want is "Choose your own god dang powers"
Btw this is from a terrible touchscreen keyboard so story for typos.
honestly I think infamous 3 has to follow cole McGrath or atleast have him be an important character in the storyline other wise it would just be another random superhero/villain game. but like I said before time travel will be involved one way or another.