Mata'u was selected in the Black Ferns 28-player squad that played the Wallaroos in a two-test series in October 2016.[1][2] She made her international debut for New Zealand on 22 October 2016 against Australia in Auckland.[3][4] She scored her only international try in a test against Canada on 23 November 2016.[5][6]
In 2018, Mata'u featured in a YouTube video that highlighted her fending off five defenders in a try-scoring run by the giant prop for her Portuguese club, Sporting.[9][10]