Wi made her junior international debut at the 2018 Asian Open Trophy in August, where she won the bronze medal behind teammate Lee Hae-in and American Gabriella Izzo. She then received her first Junior Grand Prix assignments, placing fourth at both 2018 JGP Czech Republic and 2018 JGP Armenia. Competing as a senior domestically for the first time, Wi placed sixth at the 2019 South Korean Championships and was not selected for the 2019 World Junior Championships team.
