We know that Kingdom Hearts 3 is not going to be the end of the series. In fact, Tetsuya Nomura says that Disney has not given any indication regarding putting an end to the series in a recent interview with GamesTM.
In the same interview, Nomura has hinted that the game might have one more playable character as compared to the last game in the series.
He was asked that since KH1 had one playable character and KH2 had two, could Kingdom Hearts 3 have three playable characters? His reply was not a direct confirmation, but there was a fair hint in it that there will be.
It’s a secret but by saying that we imply that maybe something’s going on. We can’t disclose anything but, maybe, something will happen there.
That is not all, Nomura also commented on the modifications that have been made to the battling system of the game. He says that while some of the changes that have been made are a result of his own creativity, there are others that are in line with the story.
For instance, he says that the Keyblade Transformation goes in line with the story because it “is involved around the plot point where Sora has gone through a test of mastery.” They have also looked into spin-offs:
There have been many bold additions to Kingdom Hearts III in combat and those are only possible because we have access to the better hardware but it hasn’t necessarily been things I couldn’t have done then. It’s more that I learned from the experiments of the spin-offs.
Kingdom Hearts 3 is being developed for Xbox One and PS4 but there is no official release date yet.