Square Enix is very interested in porting Final Fantasy XV to the Nintendo Switch, so it's actively discussing the port with Nintendo. The game's director, Hajime Tabata, said the company has been running tests to see if the Switch port is possible. Even though the system isn't as powerful as the Xbox One or PS4, it could still get the game.
We're actually doing very specific technical investigations into what's possible at the moment. [W]e've completed those tests and have worked out where the ground lies. We're currently in the middle of the discussion and debate about what we should be doing, and how to realise that on the Switch. - Tabata
Since Square Enix is still having "very open, frank discussions" with Nintendo about "what they think is the best thing to do," no announcement can be made.