McKenna made her debut for the
England national team in August 2011 in a 15–11 victory over the
United States. She also played for the country's
rugby sevens team the same year and focused on sevens for some years after. She played in the
2015 Women's Six Nations Championship in which England came fourth. In 2015, she was also part of the team to finish third in the first round of the Rugby Europe 7s Grand Prix, but was forced out for nine months due to an ankle injury. The same injury caused her to miss the
2016 Summer Olympics. She returned to international rugby in 2018, playing in three
World Rugby Women's Sevens series events. She was also selected for the England squad playing in the
Rugby World Cup Sevens in San Francisco that year, in which the team placed ninth. That same year, McKenna played for England in the Super Series in the USA. She was one of the first 28 players to be offered a full time contract by the Rugby Football Union (RFU) as they were first offered in 2019. She was named in the
England squad for the delayed
2021 Rugby World Cup held in New Zealand in October and November 2022. ==Club career==