If Assassin's Creed makes a good amount and has great critical scores across, could that usher in the new trend of game adaption films after this past decade of CBMs? We're getting a Tomb Raider reboot next, so it's possible. Imagine a Gears of War live-action amirite?
And yes, I do believe it was mentioned that AC film will be part of the universe and continuity set in the games. Since each game takes place at a different time and place, it does make it easier for different mediums to be from the same universe, since they're all mostly standalone stories anyway, aside from a few references made to characters from other games. Would be a pretty sweet easter egg if Fassbender's char makes a reference to Ezio.