Sasuke was at this point basically a better version of Lee without weights. Lee was weaker and slower than in his fight against Gaara because of the operation. So no, he'd loose badly.
Base Gaara already lost to Sasuke.
Shikamaru? Are you serious? And what? It would be easy? Lol
Sasuke isn't a better Lee, Lee improved his taijutsu as time went on and using the gates would make him do what he did to Sasuke in their first fight which is move too fast for Sasuke to react but you are right, at that time Lee was weakened but if he used Drunken Fist and the gates then he could beat Sasuke. Neji takes the fight, Sasuke copied Lee's taijutsus and Neji already beat that easily. Lee said gentle fist was Konoha's strongest taijutsu style as well so Sasuke gets in close and Neji would block and hit Sasuke's chakra points as he did to Hinata as they fought in taijutsu. Rotation and 64 palm wins this.
You do know Gaara wasn't mentally stable when Sasuke fought him right? He was after being influenced by Naruto and nothing Sasuke has is beating Gaara at that point when he shattered Kimimaru's strongest bone spear. Sand tsunami will bury Sasuke and Sand burial would kill him. Gaara could fly at that point too as he was flying on his sand with Lee when Kimimaru's summoned his bones on the ground. Post Chunin exam Gaara>partial transform Gaara. Shikamaru does have a chance at beating Sasuke, his smarts was helping him outclass smart, skilled, and strong ninjas such as Temari and Tayuya. He would keep his distances, use exploding kunais, use flash bomb which will cause Sasuke to close his eyes while shadow possession binds Sasuke then he chokes Sasuke until he pass out.
