[1] In June 2020, at the senior Swedish National Championships, conducted in a virtual format, Nystrand won gold medals and nationals titles in the 200-metre breaststroke, 200-metre individual medley, and 400-metre individual medley, as well as a silver medal in the 200-metre backstroke.

[6] At the 2020 European Aquatics Championships, held in May at Danube Arena in Budapest, Hungary, Nystrand placed 26th in the 200-metre individual medley with a time of 2:16.34, which was again faster than the 2020 Summer Olympics selection time and was attained in the qualifying period.

[6][9] Two months later, in July at the 2021 European Junior Swimming Championships held in Rome, Italy, she placed sixth in the final of the 200-metre individual medley with a 2:15.08, eighth in the final of the 400-metre individual medley with a 4:50.04, tenth in the semifinals of the 200-metre breaststroke with a personal best time of 2:31.65, fourteenth in the 4×100-metre medley relay, swimming the backstroke leg of the relay, 34th in the 100-metre backstroke with a 1:05.70, and did not start the 200-metre backstroke.

[12] The following year, as a 16-year-old at the 2022 European Junior Swimming Championships held in July in Otopeni, Romania, Nystrand competed in seven events, including placing fourth in the final of the 200-metre individual medley with a 2:14.84, fourth in the final of the 400-metre individual medley with a 4:47.65, twelfth in the semifinals of the 200-metre backstroke with a personal best time of 2:17.13, and 20th in the 200-metre breaststroke with a 2:35.54.

[20] On the third morning, she ranked ninth in the preliminaries of the 200-metre breaststroke with a time of 2:33.35 before withdrawing from further competition in the event.