Kydonaki competed in the girls' +59 kg event at the 2018 Summer Youth Olympics held in Buenos Aires, Argentina.

In 2022, Kydonaki won one of the bronze medals in the women's +68 kg event at the European Karate Championships held in Gaziantep, Turkey.

[2] A month later, she won the gold medal in the women's +68 kg event at the 2022 Mediterranean Games held in Oran, Algeria.

[3][5] Kydonaki competed in the women's +68 kg event at the 2023 European Karate Championships held in Guadalajara, Spain.

[6] In the same year, she competed in the women's +68 kg event at the World Karate Championships held in Budapest, Hungary.