JAIF

I may be going on a limb here, but assuming Kisame uses Suiton: Bakusui Shouha, Sasuke could possibly fry him with Chidori Nagashi - the water can be used as a conduct for an electrical current.

In terms of ability, we have Kisame, a rather straightforward shinobi who excels in ninjutsu, taijutsu, stamina and chakra, Sasuke, a skilled genjutsu user with quite an affinity for ninjutsu and taijutsu as well, and Orochimaru, a user of unique techniques of various forms and purposes. Kabuto doesn't even count - he'd be tossed aside like nothing, just like it happened in the fight against the Yonbi.

There is no way Sasuke would just... capture Kisame in a genjutsu, not after spending so long with Itachi, so Sasuke would have to rely on his Kusanagi no Tsurugi to fight from a distance because closing in would be suicide. Kisame would probably deflect the Kusanagi blades like nothing with Samehada, then unleash a virtual maelstrom of water-based ninjutsu that offer him an extreme advantage against any Katon techniques Sasuke would pull off, essentially pinning him and Orochimaru down to a spot, and then he could close in with his monstrous speed and start beating them down - CS2 Sasuke could probably take a lot of punishment, and Orochimaru isn't just the type of shinobi you could simply beat to death, and there will be danger for Kisame, mostly with multiple snake summonings etc, but then again, after seeing his performance against the Yonbi, Kisame wouldn't have trouble with those - more ninjutsu. And with Samehada's ability to shed the chakra off the opponents, even if it doesn't directly strike them, I can say that Sasuke and Orochimaru will be pretty much screwed up after a while, while Kisame's beastly stamina will allow him to keep going on, eventually killing them.

If you want to go on a limb, a hypothetical scenario where the pair would stand a good chance of victory would be:

Post-Orochimaru absorption CS2 Sasuke and healthy Orochimaru with Edo Tensei (Shodai, Nidai Hokage) and Manda. Of course, this is impossible, so it's just on a hypothetical level. Under these circumstances, Kisame would be in trouble, considering it'd be a water-style contest against Nidaime that normally Kisame would win easily, but he'd also have to contend with Shodai's Mokuton ninjutsu, all the stuff I mentioned above, and Manda to boot...