Ok now based on new theories I think it like this:
Sasukes genjutsu would be useless against Pein cause he couldnt cast genjutsu on 6 paths at the same time
and Pein would use his absorbtion jutsu to dispel Chidori,Amaterasu,Susanoo
Sasuke taijutsu would be useless against Shinra tensei
->Sasuke couldnt harm Pein in any methods he has known so far

sasuke would be completely crushed and i like your theorie dunsi

ok good theory but its not 100% it goes like this:
Pein might be able to absorb Sasukes Chidori but he cant absorb his sword and he is rendered defenseless while using his absorption and he prolly cant Absorb Amaretasu or Susanoo so those could possibly work which would help alot and i think he is fast enough to take out at least 4 of the six paths without them reacting!!!!

well if pein used his 6 bodies at the same time and sasuke and naruto are about the same power so im guessing that pein would win no one attack me *cough undead Cough*

pein is a cool !

Sasuke, Madara and Naruto is more stronger....

Sasuke because i think he is just like naruto in the since that he is a cheat sheet and can defeat nearly anyone although he doesnt have as big as a cheat sheet as naruto. I think it would be tie