Kages win this.
The mistake was putting them in the dessert and not restricting gaara or his dad. Hashirama will have his hands full trying to not get caught AND SEALED by gaara and his father. It will be impossible for him to attempt to counter the other kage while he is spending all his time running from sand and gold.
Muu easily has an advantage with his invisibility, raikage's easily can blitz a distracted hashirama, Hashirama has no counter for Trollkage's genjutsu/Jokiboy combo, ect.
There is too much talent on the field for Hashirama to win and the Location is a HUGE disadvantage to hashirama. Kages win with Mid - High diff