There have been a couple forum topics debating whether the dragon knight or Divine (or both/neither) should be the one dealing with Damian in Divinity 3. Personally, I think a new character would be much easier to balance the game for, without having to come up with some excuse to reset the Divine One's abilities or introduce opponents which could challenge someone blessed by the gods with the save or destroy the world. It would make more sense IMNSHO to have the Divine and Damian locked in n even battle, and a new character tasked with gathering a new council of seven, or something, to tip the balance of power.
If the player character will be a dragon knight, or otherwise able to fly, then a third person camera would work best. Otherwise, just being a sequel to Divinity 2 wouldn't make that camera style any more likely than isometric.
There have been earlier mentions of Divinity 3, but from
Divinity – Original Sin revealedThe next cause for surprise was that Divinity – Original Sin wasn’t a continuation Divinity II: The Dragon Knight Saga. That was one that could be predicted. I could tell you a lot of blah of how we needed to first fill in some gaps in the storyline before we end the story of Damian & his father, but the main reason is that we really did feel like doing something different. I know that some people feel disappointed that they have to wait a bit longer, especially those who only got into Divinity because of DKS, but the desire to go back to the first Divinity was quite strong, especially since there’s so much stuff we can do now which we couldn’t at the time.
For awhile after 'project E' (Original Sin) was announced, people in the forum assumed it would be Divinity 3. Even before FoV and DKS were released it was known there would be a third Divinity game to finish off the story with Damian.