Aww man, I liked the dialogue "You're comparing yourself to me? HA, you're not even good enough to be my fake"They're definitely changing up the story from Sonic Adventure 2 (which is fine).
It also doesn't look like the government is confusing Shadow with Sonic (which was always the dumbest part of the plot) nor does it look like Robotnik is the one who broke Shadow out like in the games.
I'm fine with them not following the exact story from the games though, gotta streamline things for a 1-2 hour movie.