I think it's likely that Itachi may as well have EMS in this battle. Given that EdoT seems to bring people back like they were in their prime it's likely that this Itachi is much younger/more powerful than the version that fought Sasuke. I don't think we will see much if any degradation in Itachi's ms during this battle.
I do agree here, since the fight with kabuto began itachi seems to have had his ms active almost all the time, seeing as he is edo tensei and ms jutsu are essentially free-of-charge for him, its almost like itachi has EMS too, so they can both fight with no restrictions on their ms :] pretty badass, its why i know if hey went all out together they would squash kabuto but they have to keep him alive
not that sasuke is doing a very good job of listening
