As of this writing, Gwen hasn’t confirmed nor denied whether she’ll return for Season 23 of The Voice, but if her history on the show is any indication, it’s pretty unlikely.
Throughout her years-long tenure on the series, she’s never stuck around as a coach for consecutive seasons.
The mother of three made her debut in Season 7 alongside Adam Levine, Pharrell Williams, and her now-husband, Blake. Later, she returned for Seasons 9, 12, 17, and 19. She was also featured as a part-time advisor on Seasons 8 and 10.
Source: https://www.distractify.com/p/why-is-gwen-stefani-leaving-the-voice