Thanks to the recent introduction of six new voice choices, Google Assistant now features a total of eight such options — four female and four male voices. Even more, Sundar Pichai has confirmed at Google I/O that John Legend's voice will also reach the company's virtual assistant by the end of the year.
https://www.notebookcheck.net/John-Legend-coming-to-Google-Assistant-later-this-year-six-new-voices-already-available.303106.0.html