Lmao, The World that Never Was. Amazing. :lol
Anyway, Sasuke wins. Comfortably.
-B was getting damaged by the Bijuu's attacks and Madara was about to run him through with a Susanoo blade. So he won't be tanking Sasuke's sword slashes. Blocking with his tails won't help since far weaker things have cut through his tails like they were butter. Multiple sword slashes right to the body and B is pretty much finished. Not sure if Sasuke's PS can use arrows or not, but if it can, then a single arrow is all that is needed since it's too fast to dodge and it'd be much stronger than his regular sword slash just how his regular arrow is much stronger than his regular sword slash.
-Bijuu Dama is no issue since PS would tank B's Bijuu Dama. Naruto and Sasuke's Chidori and BD were equal and when they clashed both attacks enveloped them. PS came out with a messed up wing, arm and half of the face was blown off. Scale down to BM and PS by removing the Rikudo Boost, and Sasuke's Susanoo would replicate the same feat. So if B wants to even do that much damage to it, he'd have to use 2 BD's the size of what Naruto used (relative to his own size) in VoTE.
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than a regular standard (Full Kurama's is much bigger than B's standard, but
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was the same size as Full Kurama's.) when it comes to the ball's size and the explosion's size, so Continuous BD isn't doing anything significant to PS.
So unless B makes a BD that size and uses it twice, he won't achieve the level damage that PS took in canon. His biggest BD is nowhere near this size. Continuous BD is only going to barely reach that level.
CBD: [
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]
SBD: [
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Sasuke simply cuts apart B while taking his offense, and given Sasuke's offensive power, it shouldn't take long for B to kick the bucket.