An Edo vs Edo fight between these two...? people often forget that Edo Itachi receives arguably one of the best power ups thanks to Edo Tensei. Constantly having his chakra regenerating. While all edo's get this, Itachi has a large move list and a considerable amount of his stronger moves eat away at his chakra.
When an Edo Tensei, he can basically spam like Sasuke did. But without draw backs.
Minato has nothing that can get past Susano'o. I keep hearing people say he can teleport it away and I don't understand how he can. Unless he sets up a S/T barrier and Itachi runs into it... Which would teleport Itachi too.
KCM is not something that is spam-able. The chakra will run out, and I'm unsure if it can come back. It seems he only has the chakra, not the bijuu. And it takes Kurama some time to regain his chakra. I doubt there is some ability Minato has that will regenerate the chakra at a quick rate.
At best, I say a portion remains and slowly, as time goes by, grows naturally.
And once KCM is out, it comes down to a normal Itachi vs Minato thread. Minato's chakra reserves are something we're not sure of, so we don't know if Edo Tensei gives him the same boost it gives Itachi. And with unlimited chakra, and the ability to just destroy the kunai with ease... Itachi takes this.
Minato could potentially avoid attacks like Amaterasu (If he gets hit) by using his S/t barrier. But really, without his FTG marked Kunai, it's only a matter of time before Itachi manages to land a deadly blow.
And once this occurs, Itachi will use the time he has to seal Minato with the Totsuka Blade. After all, Minato will not be the most responsive while regenerating.