Sasori has 298 human puppets, Human puppets retain their jutsus, just like the 3rd Kazekage. Bad thing we didn't get to see those other human puppets, we couldn't tell whether one of those remaining 297 has jutsus that will be troublesome for Orochimaru. However, he is cunning, and his Performance of a Hundred Puppets & "3rd Kazekage w/ Iron Sand" human puppet proved to be devastating. Also his puppet mechanisms are amazing, and he can regenerate unless his weak part isn't destroyed yet.
Orochimaru, on the other hand, has many techs that were already proven to be useful and effective, and has arrays of jutsu, from offensive (Wind Release: Great Breakthrough, Twin Snakes Mutual Death Tech, Sword of Kusanagi, Many Hidden Shadow Snake Hands, 10,000 Snakes) to defensive (Triple Rashomon, 10,000 Snakes) to supplementary (Manda, Impure World Resurrection, stretching and bending his body, reconnect his body when bisected, shedding his skin to heal injuries). Plus, he is cunning, and has amazing regenerative ability. And of course, the Eight Branches/Hydra Technique.
With that, I can see that Orochimaru will win it, but with great difficulty. However, if only we get to see what are the other human puppets' abilities, that may be another story.