By edos your talking about: 2nd Mizukage, Muu, 3rd Raikage, and 4th Kazekage, right? If so, hokages win. 6v4, and if you take it like this (MY OPINION)...
Hashirama>4th Kazekage
Tobirama, Danzo > 2nd Mizukage
Hiruzen in prime> 3rd Raikage
Minato, Tsunade>Muu
So as the battles start, Hashirama and Gaara's dad are battling, and Hashirama wins. The rest of the kages are still fighting. He can go help against 3rd raikage, because I'm pretty sure Hiruzen+Hashirama>3rd Raikage. 3rd Raikage may be able to injure one of them or both, but he still dies. If Tobirama and Danzo are having trouble (I'm pretty sure they won't) Hashirama injured+Tobirama+ Danzo> 2nd Mizukage, but one of the first 2 may die.
If that happens, its still 5v1, and by this time one of the hokages fighting Muu might be dead or injured. Anyways, Muu can't win against 4 hokages, especially hiruzen in prime, Minato or Tsunade, Tobirama or Danzo, and Hashirama,
* By defeating them I do mean sealing them.