Tsunade wins mid difficulty.
You must be registered for see links
was
You must be registered for see links
. That shield isn't even meant to break through tough defences unlike Tsunade whose punches proved to be the strongest weapon that the Gokage had against susanoo barring Onoki's jinton.
Kimimaro can evade Tsunade's hits and tag Tsunade but ordinary stabs aren't coming close to killing her. He isn't fast enough to blitz SRA Gaara let alone Tsunade so she isn't going to have her head blitzed off. With the usage of ground punches to throw him off, as well as superior stamina, Tsunade will eventually finish him off.
If Kimimaro opts to use bone forest, Tsunade can destroy any bones near her by punching them so that when Kimimaro emerges from a nearby bone, Tsunade will have enough time to react to Kimimaro's strike.