Itachi takes this with mid difficulty. I'm not sure if Chiyo can fight Itachi without looking at his eyes or hands. Even if she could, it would be increasingly difficult for her to keep up with Itachi's speed. Most of Itachi's ninjutsu can be blocked with chakra shields though since they were strong enough to block iron sand which is much stronger than any ninjutsu in 3 tomoe Itachi's arsenal.
Itachi's hand seals are very fast allowing him to create a crow clone while undetected and have it shunshin behind Chiyo to blow her up. Of course, Itachi can blind her with katons to give himself openings to carry out the aforementioned strategy.
