He won't be punished. Sasuke is helping save the world, and was a key figure in the defeat of Obito and will obviously play a part in Madara's defeat. That will make up for the past sins. People also forget that all Sasuke did was breaking and entering at the Kage Summit. He just wanted Danzo, the Samurai and other Kage attacked him first.
Not only that, but ninja murder all the time. Sasuke never did what any of the other ninja villages haven't done, Konoha has killed, Kumo has kidnapped(A has even compared kidnapping Bee the incident of when Kumo tried to kidnap Hinata), Kirigakura had their children slaughter each other, Suna attempted to destroy Konoha with Otogakure, and Iwagakure used organizations like and including Akatsuki. They forgave each other for that because they helped each other in the war, so they can forgive Sasuke.
Even Gaara, a mass-murderer and one who helped in the attempted destruction of Konoha, was forgiven just for trying hard to be. Sasuke definitely won't be punished.