Hansson competed at the 2016 Olympic Games in Rio De Janeiro and helped team Sweden finish 5th in both the 4×100 and 4×200 freestyle relays. Her best individual finish came in the 200 IM where she finished 29th with a time of 2:15.66. She has been a part of silver-medal winning 800 freestyle relay at the 2014 FINA Championships. That relay also broke the European Record. At the 2014 European Championships, Hansson swam in the 4×100 freestyle relay that ended up taking the gold. She is also a two-time junior European Champion in the 50 butterfly.
2017 NCAA Championships
To finish off a successful freshman season, Hansson helped Southern Cal finish ninth at the 2017 NCAA Championships. She got third in the 100 butterfly with a time of 50.45. She also competed in the 200 IM where she finished seventh and 100 freestyle where she won the B-final in a 47.30. On the last day, she lead off the Trojans’ 400 freestyle relay with a time of 47.07 and they got in fourth place.
2018 NCAA Championships
In Columbus, Hansson competed in the 100 and 200 butterfly and all five relays. She won her first individual title in the 100 butterfly and joined the sub-50 club with a time of 49.90. On the last day, she finished third in the 200 butterfly behind Ella Eastin and Katie Drabot.
2019 PAC-12 Championships
In Federal Way, Hansson went 3-for-3 in individual events, including breaking the NCAA and US Open records in the 100 fly, clocking a 49.34 for the fastest time in history. She also won titles in the 200 IM ((1:52.50) and 200 fly (1:50.68), breaking the championship record in the former.
2019 NCAA Championships
In Austin, Texas, Hansson set the NCAA, US Open and Pool records in the 100 butterfly, winning in 49.26. She also set the pool record in the 200 butterfly (1:50.28) in another gold medal winning effort and finished fourth in the 200 IM (1:52.14).
Hansson also was part of USC’s third place 800 freestyle relay and on the ninth place 400 medley relay and 400 freestyle relay team.