>>28137630The anime confirmed multiple Zygarde exists.
Perfect Zygarde confirmed the number of Zygarde is 5.
The official site implies 50% consists of 2 Cores, evidencing these 5 Cores will also exist in the games.
GameFreak has officially stated that Zygarde will play a role in SM.
So yeah, some of them might just be Alola Zygarde, while others are Kalos Zygarde.