Hebi Sasuke & Kimimaro should take both scenarios.
Hebi Sasuke is capable of taking them both down, but he needs Kimimaro to distract the other while he does this, which shouldn't be too much of a problem. If he goes for Tsunade, he should be able to off her in a relatively short amount of time (while Kakashi is being pressured by Kimimaro). Hebi Sasuke outclasses Tsunade by a fairly large margin in almost every aspect. He's much faster, will NEVER get tagged, and has the ability to nullify Byakugo via decapitation w/ his raiton flow Kusanagi. She's basically a sitting duck to someone who kept pace with Itachi and possess highly advanced shunshin that dwarfs her own. She is outmaneuvered and diced to bits. Honestly if Sasuke decides to coat his blade in lighting and run at her swinging there isn't much she can do to stop it. They tag team Kakashi after Tsuande is dealt with. Should Kimimaro die in his skirmish with Kakashi, Sasuke goes CS2 and ends the copy ninja as well.
Not much changes with scenario 2, except the difficulty at which Sasuke & Kimimaro win.