In 2021, Semeraro qualified at the World Olympic Qualification Tournament held in Paris, France to compete at the 2020 Summer Olympics in Tokyo, Japan.[10][11] At the Olympics, she finished in third place in her pool during the pool stage in the women's +61 kg event and she did not advance to compete in the semifinals.[6] In October 2021, she won the gold medal in her event at the 2021 Mediterranean Karate Championships held in Limassol, Cyprus.[12][13] In November 2021, Semeraro won the silver medal in the women's 68kg event at the World Karate Championships held in Dubai, United Arab Emirates.[14][15] She also won one of the bronze medals in the women's team kumite event.[15][16]