The latest Pokémon, Sun and Moon, will have the first footage aired in Japan next month.
The variety show Pokémon House airs in Japan every Sunday, and will reportedly show off footage April 3rd. Director Junichi Masuda will be on the show alongside Battle Director Shigeki Morimoto.
Joining them as well will be Shigeru Ohmori, director of Omega Ruby and Alpha Sapphire. The three will be on to discuss the new games, and will feature the first footage seen of Pokémon Sun and Moon. (source)
It’s unknown whether Nintendo will show off the games before April 3rd, but with a Holiday 2016 release date in mind it’d be unlikely that they are in a rush to show the new additions to the franchise off.
So far the only details known of Pokémon Sun and Moon are the titles. Nintendo has been keeping the details to themselves, but expect that all to change this summer.