In 2018, she chose to represent Slovenia. On July 31, she officially received her Slovenian citizenship. This gave her the opportunity to start competing at international competitions. In August, she competed at World Cup Kazan in Russia. Katya placed 8th in All-around and qualified to two apparatus finals, where she placed 5th with Hoop (18.950) and 7th with Ball (17.800). In September, she competed at the 2018 World Championships, which was her first one. She helped Slovenia to achieve the best result in Team competition so far, placing 11th together with teammates Aleksandra Podgoršek and Anja Tomazin. She also placed 17th in All-Around Qualifications and qualified to the All-Around Final where she placed 13th, which is also the best result for Slovenia.