So She would be punching off her own head? good to know she's an immortal....oh wait she isn't so any kill blow landing on Hidan would just transfer to her and as i said before defeating herself.
Provided he is in his cirlce. I wonder. What if she 1st smashes the ground breaking the circle beneath him (I doubt Hidan is going to continue to stand in a shattering circle when it starts to fissure) then, like she did with the Juubi minions catches him in mid air with a solid punch to the head exploding it. Does his curse abilities still work then or does Sakura score the hit?
Also everyone says Sakura gets beat by Hidan because he can just cut his own head off or stab himself over and over to keep her from moving. So than Sakura has no intel on Hidan but Hidan has all the intel on Sakura?
How would Hidan know to continuously strike at his body to stop her. He is more than likely going to stab himself in the heart or stomach. Sakura's Byakugou is going to counteract allowing her to tank it and continue her assualt.
Hidan would be momentarily perplexed at why she isn't on the ground writhing in pain and Sakura is going to juse that opening for a counter attack of her own. This is a possiblity.
Not saying it's an easy win or a stomp, but that goes for Hidan too. This is a good 50/50 fight where either of them could win. So yes Sakura is the perfect counter for Hidan's curse given no intel on either's abilities.
The only problem is that I don't see her understanding the curse (the symbol in the ground part) before she runs out of chakra
Now this is a really good point. But it works both ways. While she may not understand the curse. Hidan is not going to understand why she wont stay down when he ganks himself.
This is time both will no doubt be using to learn and understand each others techniques. I believe this is a really good match up to be honest. Once Sakura learns how the jutsu works (and she will she is an analytical fighter as well) Then it's a matter of disrupting the circle before Byakugou runs out.
Same for Hidan. Once he learns how Byakugou works, it's a matter of creating the circle and inflicting a depcapitation to end Sakura. Really this battle could go either way.