I'm kind of conflicted on this one ...
Playstation-oriented franchises have been really popular recently. Disney has become bigger than ever before, which is saying a lot, because they've always been the biggest entertainment company in the world. But now with Star Wars and Marvel they're even bigger.
Kingdom Hearts COULD sell as much as a crossover game like Smash Brothers. Will it? It's hard to tell, but it's definitely a possibility. I feel like the make or break is if people can get over it being a JRPG, yes, even an action oriented one. Final Fantasy this generation has been hugely successful, but not as successful as many people were expecting. Can it get over that? Maybe. I think Final Fantasy 15 will get past 10M with PC, I'm not sure if KH3 can do that without PC.
God of War has the potential to sell 11-12M lifetime.