Octavian's arrivals are not, in fact, anywhere near as flashy as those of his little sister. He's not even as flashy as Tidebringer. He isn't trying to be flashy at all, he's just trying to be efficient.
This does not exactly stop him from being more impressive than almost anyone else you could name.
First, there is not an Octavian there. Then there is. (There are levels of speed that are difficult to distinguish from teleportation.) He has extremely close-trimmed hair and an extremely close-trimmed beard and earbud headphones is wearing small round glasses which serve to amplify his sheer disapproval at the sloppiness and incompetence in every part of this battlefield, emphasizing his absolute focus on whatever he's doing. He's within five feet of one of Livia's troops and the man with the stunner goes back against the wall and up simultaneously and collapses in a heap. Then he's next to another one. Then another. His flying near-teleports are punctuated with motions, precise arm gestures that bring his hands close to whoever he's hitting but never touching, which is irrelevant, because the air (funneled by his touch into whirlwind blasts) touches them for him. He is not bothering to waste punches - if he's within arm's reach of someone, they are already out of the fight, and he's moving on to the next.
That "huh" is barely finished by the time the last of Livia's troops outside the bubble is unconscious.