Swenn-Larsson attended the ski school in Järpen , started for the ski club in her hometown Rättvik and has been a member of the Swedish Ski Association's World Cup group since 2012 . She has been taking part in FIS races since December 2006, and celebrated her first victories in April 2007. From next winter she came to the European Cup , but initially remained without points. In February 2008 she became Swedish junior champion in slalom. Swenn-Larsson won her first European Cup points with 13th place in the indoor slalom on November 20, 2009 in the alpincenter Hamburg-Wittenburg . A little later, she was among the top ten for the first time in the two Funäsdalen slaloms . From 2008 the Swede took part in the Junior World Championships . Her greatest success was achieved in 2011 in Crans-Montana by winning the silver medal in the slalom. Her greatest success to date at national level came in April 2010 when she became the Swedish slalom champion in Björkliden , leaving world-class runner Maria Pietilä Holmner behind by three hundredths of a second.
On December 11, 2010 Swenn-Larsson reached her first podium in the European Cup as second in the Gressoney slalom . Ten days later she competed in her first races in the World Cup and immediately won World Cup points in the Courchevel slalom with 26th place. She finished the 2010/2011 European Cup season in fourth place in the slalom and eighth place overall. Since the winter of 2011/2012 Swenn-Larsson has been regularly competing in the World Cup in the disciplines of slalom and giant slalom. While she was still without World Cup points in the giant slalom, she was able to catch up with the extended world elite in the slalom. At the end of the 2011/2012 season , she achieved her first top 10 results in the World Cup with ninth place in the Åre slalom and tenth place in the Schladming slalom .
Her first podium finish in a World Cup race was on March 8, 2014 when she finished third in the Åre slalom . Previously, on February 25, 2014 in Innsbruck, she and the Swedish team celebrated a victory in the team competition against Norway and Switzerland , which is only part of the Nations Cup . As a result, Swenn-Larsson could no longer build on previous achievements and lost the connection to the world elite. Her top 10 placements in World Cup slaloms only sporadically, which is why she started more and more in the European Cup. In the 2016/17 season she won the Slalom European Cup.
In the 2017/18 World Cup winter , Swenn-Larsson showed a strong improvement with a total of nine top 10 placements, and at the 2018 Winter Olympics she was fifth in both slalom and team competitions. She was able to maintain this high level in the 2018/19 season . The highlights were second place in the World Cup slalom in Maribor on February 2, 2019 and two weeks later winning the slalom silver medal at the 2019 World Cup in Åre .