Stubailo joined the main group of Russia's national rhythmic gymnastics team in 2019. She competed at the 2019 European Games in Minsk along with Vera Biryukova, Anastasia Maksimova, Anastasia Shishmakova, and Maria Tolkacheva. They won the gold medal in the group 5 balls event with a score of 27.300, but they only placed 5th in the group 3 hoops and 4 clubs. They won the bronze medal in the group all-around behind the Belarussian and Bulgarian groups.