I never actually cared to measure how fast characters move in comparison to the others HOWEVER I remember back in the T6 board a lot of people were talking how some people had much better side stepping than others.
I recall this in particular because I was still in the beginning (not that i'm much of an advanced player now but at least I consider I know the basics) and was looking for detailed information regarding Lili.
A lot of people even on Tekken Zaibatsu were bringing up the fact how Lili has one of the best side stepping in the game compared to other characters. So if in T6 different characters had better or worse side stepping than each other, it would be safe to assume they didn't just take away that particular aspect.
So I would be inclined to believe that even in TTT2 characters have slight different in their movement.
PS : I also remember how there was this topic on forums about the Korean tier list who unlike the other tier list placed Alisa much higher than other tier list simply because of her very good movement and maneuverability (my bad if i misspelled this word xD)