In November 2017, he was named in the West Indies squad for the 2018 Under-19 Cricket World Cup.[3] Following the West Indies' matches in the tournament, the International Cricket Council (ICC) named Athanaze as the rising star of the squad.[4] He became the second batsman for the West Indies to score two centuries in one tournament, and finished as the competition's leading run-scorer, with 418 runs.[5][6]
In February 2023, Athanaze was selected in West Indies Test squad for the South Africa series.[11]
In May 2023, he was named in West Indies' One Day International (ODI) squad for the series against United Arab Emirates.[12] He made his ODI debut in the third ODI of the series, on 9 June 2023.[13] Athanaze impressed, scoring 65 runs and equalling the record for fastest ODI half-century on debut.[14] In December 2023, he scored 66 runs off 65 balls in the first match of the ODI series against England to lay a strong foundation for the West Indies, who successfully chased a target of 326 runs, winning the game by 4 wickets.[15]
In December 2023, he was selected in West Indies squad for the test series during their tour of Australia.[16] In the first test, he only managed to score 13 runs, all of which came in the first innings, as he scored a duck in the second innings.[17] In January 2024, he was selected in West Indies's squad for the ODI series against Australia.[18] He opened the batting for the West Indies in the first ODI and scored just 5 runs from 11 deliveries.[19]