MUa

On October 24, 2018, Chaehyeon, then known as Yeon Chae, was introduced as a trainee under All-S Company and a member of their upcoming girl group, ALLS-GIRL. However, by early 2019, two members departed from the group lineup and soon after, their SNS accounts became inactive and the agency no longer mentioned the girl group, signifying that they have disbanded without any official announcements. On July 9, 2021, Chaehyeon was revealed as a member of the upcoming four-member girl group SKYLE under Good Luck Entertainment.

The group made their debut in August 4, 2021 debut with the single "Fly Up High". On May 17, 2024, Chaehyun shared a teaser for her first digital single "Like Salad", to be released on May 24. She subsequently announced that she had changed her stage name to MUa.