Kabuto can't maintain control all of his ET in a combat situation. I wonder how many he could control while his fighting style isn't hindered. If he plays his cards right he has a chance actually. If he puts Mu, 3rd Raikage, Nagato, Itachi and Deidara and manages to control them while himself assumes a support role he can win. It all depends their teamwork.
Nagato can bug Hashirama with a CT.
3rd Raikage would try to chop Buddha's leg to make it lose balance.
Itachi and Mu can assist Raikage and Deidara sets for C4.
Its a grand scale battle so many outcomes. But in all scenarios Hashirama definetly can't neg Kabuto.