Seven new Pokémon have leaked out before the July 1st announcement, The 7 new pokemon are listed below along with screenshots.(all images have been taken from the new gameplay footage of Sun and Moon leaked via 4chan.)
The seven new Pokemon are as follows:

Tapukoko: an Electric/Fairy type

Charjabug: a Bug/Electric type bug

Vikavolt: a Bug/Electric type

Drampa: a Normal/Dragon type.

Bruxish: a Water/Psychic

Cutiefly: a small Bug/Fairy type

Togedemaru: an Electric/Steel