In her second and final year of high school, she won the All Japan High School Championship.[1]
In 2017, Iwasawa was selected to represent Japan at FIVB Volleyball Women's U21 World Championship in Mexico where the team finished with Bronze medal.[2][3]
In March 2018, Saitama Ageo Medics announced that she would join the team.[4] As Akane Yamagishi was the regular libero on the team, she was unable to secure a regular starting position and mainly came on as a subtitute receiver.
In the 2022-23 season, she made her starting member debut in the V.League Division 1 opening match against NEC Red Rockets. The team won the match in straight-sets victory.[5] She also played as the starting libero in the second match against NEC, making a series of excellent receives and contributing to the team's winning streak. She also received the VOM (V.League of the Match) award.[6]
In 2023, she was selected as a member of Japan women's national volleyball team for the first time.[7]
In 2025, she was selected for the VNL first week's round in Canada. She was registered as an outside hitter rather than libero because she was a substitute receiver.[8] On June 8 the same year, she made her national team debut as a libero in the match against the Dominican Republic in the same round. She supported the team with tenacious defense and contributed to the team's straight-sets victory.[9][10]