In 2015 season, she competed in numerous Junior World Cup events in Lisbon, Budapest, Pesaro, Sofia.

[4] Diachenko appeared in her first senior international competition at the Miss Valentine Cup finishing 4th in the all-around.

On March 31 - April 2, Diacehnko then competed at the 2017 Grand Prix Marbella finishing 11th in the all-around and qualified to 2 apparatus final.

On May 19–21, Diachenko along with teammates Viktoria Mazur and Yeva Meleshchuk represented the individual seniors for Ukraine at the 2017 European Championships.

Diachenko competed at the quadrennial held 2017 World Games in Wrocław, Poland from July 20–30, however she did not advance to any of the apparatus finals.

On August 30 - September 3, at the 2017 World Championships in Pesaro, Italy; Diachenko finished 19th in the all-around finals.