Really, Kakashi and the entirety of Team 10 couldn't hold a finger to Kakuzu and people actually expect Neji to be able to do anything before getting decimated?
Kakuzu mid diff.
he will do the classic 4 split first and keep 1 on him.
use wind to boost fire and shoot electricity all through the field.
and use earth element to harden his own body to boost defense against neji's taijutsu.
lastly he can use water as secondary defense if he want to like a waterwall or just shoot some water tech.
Neji could use all the rotation and 64 trigram to his best perhaps take down 1~2 heart ,before his stamina and chakra start running low.