Wigness was also a part of the gold medal-winning Australian teams at the 2018 FIBA Under-18 Asian Championship and the 2019 FIBA Oceania Under-18 Championship as well as competing for his home nation at the 2018 FIBA Under-17 Basketball World Cup and the 2019 FIBA Under-19 Basketball World Cup. In his final year before turning professional he played in the 2019 NBL1 season, where he averaged 11.7 points, four assists and 3.4 rebounds per game for the Basketball Australia Centre of Excellence. In his season finale, he posted 22 points and 12 assists. Wigness was put on the radar of several college and NBA scouts when he travelled to Charlotte, North Carolina to compete in the 2019 Basketball Without Borders Global Camp and walked away with All-Tournament honours.