The Saiyans Meet Night Raid! A Tearful Reunion.

Taking place after the defeat of Majin Buu, But before the events of the Battle of Gods, Goku and Vegeta somehow ended back in time or to another Earth where they help out a group called Night Raid to help with their goal to overthrow the Empire while they try to figure a way back home. Disclaimer Don't own any of these anime/mangas