The two artists are the latest additions to the SB Projects roster following Kanye West, whom Braun began co-managing in March. Mensa is co-managed by Cody Kazarian, reported Billboard magazine.
Over the last two years, Braun has been steadily building out his management base.
In addition to longtime client and Usher protege Justin Bieber, Braun represents Tori Kelly, Carly Rae Jepsen, Martin Garrix and Black Eyed Peas, among others.
He and former client Ariana Grande parted ways in February, though Braun is credited with having A&R'd her just-released album, Dangerous Woman, along with Republic Records EVP Wendy Goldstein.