She won the gold medal in the women's kumite 68 kg event at the 2014 World Karate Championships held in Bremen, Germany.

Agier also won the gold medal in the women's 68 kg event at the 2016 World University Karate Championships held in Braga, Portugal.

[7] Agier won the gold medal in the women's kumite 68 kg event at the 2019 European Karate Championships held in Guadalajara, Spain.

[8] In November 2021, she won one of the bronze medals in the women's 68 kg event at the World Karate Championships held in Dubai, United Arab Emirates.

[12] Agier won the bronze medal in the women's 68 kg event at the 2022 World Games held in Birmingham, United States.

[14] Agier won one of the bronze medals in the women's team kumite event at the 2023 European Karate Championships held in Guadalajara, Spain.