If Tobirama could outmanuver a skilled Sharingan user using similar technique that Minato uses.
How does Harashima counter? He's eyes would have to be superior to that of a Sharingan user, in tracking movement at least.
I do think that if Minato had his Kunai all over the place, he could get one up over Harashima. Of course, this is assuming that neither knows what the other can do, so Harashima would probably start with some lower-level AoE attacks...though He could probably guess what the Kunai scattered all around would be used for.
Still. In terms of Speed, Minato has the advantage. Harashima's advantage lies in that he can almost always keep an enemy at bay using his massive AoE attacks. Also the fact that he can heal instantly helps too.