IF they fought one one on in a netural terrain who would come out victorious
The only way that Laxus can come out of this battle victorious is IF and ONLY IF he can counter Sasuke's Mangekyou Sharingan. It doesn't matter what jutsus that Sasuke can come up with. He can use all the Chidori he likes but Laxus is already lightning based so that would be dumb on Sasuke's part. It will eventually come down to his Sharingan and how well he uses it.
3 moves that Laxus has to go up against and OVERCOME in order for him to win.
Final verdict? Uchiha Sasuke wins here because I'm pretty confident that Laxus is unable to handle ALL three moves and come out alive. He may be able to handle certain illusions like he did with Mistgun but the level here is entirely different than just scenery tricks.