[14] On 7 May 2016, Fusitu'a made his International debut for Tonga against Samoa in the 2016 Polynesian Cup where he played at fullback in the 18–6 loss at Parramatta Stadium.

[18] On 11 November 2016, Fusitu’a made his international debut for New Zealand against Scotland, playing on the wing and scoring 2 tries in the shock 18-18 all draw at Derwent Park.

[19] On 20 November 2016, Fusitu’a would make his second appearance the Kiwis, playing in the 2016 Four Nations Final against Australia on the wing in the 34–8 loss at Anfield.

[23] On 11 November, in the highly entertaining clash against New Zealand, he scored a hattrick of tries as Tonga pulled off the biggest upset of the tournament, defeating the Kiwis 28–22 at Waikato Stadium.

Following a breakout performance for Tonga in the World Cup, in 2018 Fusitu'a produced the finest NRL season of his career to date with the Warriors.

[28] He was named on the wing again for Tonga in their historic first-ever Test match with the Australian Kangaroos on 20 October 2018, played in front of a sold-out crowd at Mount Smart Stadium, Auckland.

Fusitu'a missed the clubs 2022 Super League Grand Final loss to St Helens due to injury.

[34] He played a total of 17 games for Leeds in the 2023 Super League season and scored ten tries as the club finished 8th on the table and missed the playoffs.