Restricted Nagato's summonings? Not like it matters, Kidomaru's webs would have binded all of them.
Kabuto wins, if Nagato tries to pull him, Kabuto gets a clear shot for Hakugeki.
If Nagato uses ST, Kabuto tanks it with ease due to SM + Orochimaru durability.
Chibaku Tensei fails here because Kabuto just has to pull out Jirobo, and manipulate the earth so that it protects him. Once the CT is complete, he can use Muki tensei to destroy the core since all of the earth will be connected through CT.
Nagato's only way of winning this fight is soul ripping...He can't soul rip if Hakugeki counters Bansho tennin.
Kabuto can also win the same way Jman won....Sound Genjutsu.