Sanchez made her debut in major international competition in 2017, as part of the Canadian team for the 2017 World Junior Swimming Championships team in Indianapolis. She won two individual medals, a silver in the 200 m individual medley and bronze in the 100 m freestyle, and was part of a Canadian sweep of the gold medals in the women's relay events, taking gold in the 4x100 m and 4x200 freestyle as well as in the 4x100 medley. In the process the team broke the junior world record and championship record. Later that season she also competed at her senior championships, the 2017 World Aquatics Championships in Budapest. Sanchez was part of the Canadian team in the women's 4×100 m freestyle relay event, finishing fourth overall.