Team tsunade? Wtf? How is mei, temari or hinata part of team tsunade?
Team 1 has a chance of winning almost entirely due to mei. Why? Because hidden mist can nullify the sharingan and protect them from itachi's deadly precog, sharingan genjutsu, MS jutsu and help dull his reaction time... Without hidden mist, this would be a much much muccchhhh harder fight. From there, Tsunade can just basically power up temari and temari keeps tossing Kre Kre mei, inside the cover of hidden mist, until itachi goes down.
The ladies have a very good chance at this fight; Hinata, Mei and temari all play an extremely crucial role in negating itachi's arsenal.