No trailer this month, but August's trailer introduces the new gimmicks and story. The three gimmicks being mentioned around in leaks are:
1) Feral and Refined Formes: minor appearance and stat differences, and in very few cases type differences. All Pokemon minus legendaries have these. Examples: Feral Pokemon have sharper teeth, more points/spikes, Refined Pokemon have more aerodynamic/rounded/smoother features. Bill (from KANTO) makes an appearance with a machine that lets you change non-forme Pokemon into Feral or Refined Formes by 'sending their DNA back/forwards in time' (which is the major story plot because Bill constantly doing this rips a hole in space-time and lets Miraidon or Koraidon through).
2) Gem-Type: Basically megas but gives your Pokemon a crystalized form and a temporary 'Gem' type which resists all and is only weak/strong against other 'Gem' types. One use per battle. You have to collect or craft shards to power up the item that changes the Pokemon.
3) Veil Fakes: The evil team is called Team Veil, and they basically glue and tape shit to Pokemon and report rare Pokemon to lure trainers out. They got so efficient at it, there's tons of Veil Fakes out there that need to be 'purified'.
Starter evolutions won't be until September.
