The Director of Kingdom Hearts III Tetsuya Nomura shared a lot of information about the development, worlds and features of the game in an interview published in this week's Famitsu issue. Start by talking about the continuous postponements of the game. The reason why it was delayed is the result of continuous adjustments with the parties involved. It was not due to the need for more development time.
The world of Frozen it's set in the same period as the film, and the scene we've seen will be developed in the same way. There will also be "Let It Go". Anna and Elsa will not join the group but Marshmallow will lend his powers. The world of gods Pirates of the Caribbean is set during the third film. The part of Ratatouille It is a mini-game where you can create meals that will increase the statistics.
A secret film is already underway, but it is not yet finalized.
Since Kingdom Hearts III is very large there is a concern that there may not be enough space for everything. To reduce some loading times, Square Enix is working to convert some cutscenes into movies, but the volume is much greater than expected. Final Mix versions, which have added content in the past, will not be considered for this third chapter. Instead, there are plans for updates via DLC. Nomura believes that it will be simple downloads rather than a Season Pass, which will be absent.
Recall that Kingdom Hearts III will be released in Europe on 29 January 2019 for PlayStation 4 and Xbox One.