During his sophomore season at Michigan, Hughes was selected to compete at the 2019 World Junior Ice Hockey Championships, alongside his brother Jack. They became only the third pair of brothers to compete for Team USA at a World Juniors tournament, with the most recent pairing being Joey and Michael Anderson in 2017. On December 24, 2018, Hughes, along with Michigan teammate Josh Norris, were named alternate captains for Team USA. The two players were two of five returning competitors from the 2018 World Junior Championships team. Hughes helped lead Team USA to the gold medal round of the tournament where they lost 3–2 against Finland.