Does hashi know anything about pain? Still, the 6 paths could hold hashi off while nagato uses Chibaku Tensei.
Animal Path summons, especialy the dog, Could hold off the wood dragon, which was only good against kyuubi, because wood style is the perffect counter to bijuu.
Deva path can fly, so we have to assume that nagato can too, so that counters flower tree world, as pain isn't affected. Deva's ST keeps the tree's from crushing them directly.
And finaly, as nagato is flying, he can bansho tennin hashirama, then drop him from 700 feet, then he is either dead, or at pain's mercy.
7 V 1 is always hard, and with shared vision, fighting is impossible unless you have vast knowleage and invisible attacks.
And finaly, nagato can use bansho tennin on fallen pains then revive them with nakara path.