That EMS is basically Sasuke going full-force with his powers, boosting his normal dojutsu techniques, as well as giving him access to both the Amaterasu flames, and the Susanoo chakra avatar.

Sasuke Uchiha left Konoha after a battle and turned into a tree in Boruto: Two Blue Vortex. Despite his cruel fate, Sasuke is expected to return stronger than ever in Boruto after a timeskip.