Close to a return, Thorisdottir suffered a further setback when doctors picked up a rare and complicated issue with the foot that would be "potentially career-threatening" if left untreated.

[12] In September 2017, Thorisdottir left Klepp to sign a two-year contract with English FA WSL team Chelsea.

[15] In her second season at Chelsea, Thorisdottir scored her first goal for the club on 12 September 2018 in a UEFA Champions League Round of 32 5–0 victory over SFK 2000 Sarajevo.

She was part of the under-17 team during 2009 UEFA Women's Under-17 Championship qualification and was called up to the finals in Nyon, Switzerland where Norway finished in fourth place.

At under-19 level Thorisdottir was part of the team at the 2011 UEFA Women's Under-19 Championship, reaching the tournament final before losing 8–1 to Germany.

[7] Having reignited her club career with Klepp, she made a return to international football three years later, receiving a call-up to the under-23 team for the La Manga U23 invitational against Japan and the United States in February 2015.

[28] On 6 March 2015, just four days after appearing for the under-23 team in La Manga, Thorisdottir made her senior international debut starting in a 1–0 victory over Iceland.

[36] Having at least reached the semi-finals in the past four editions, Norway surprisingly crashed out bottom of the group having lost all three games, the first time they had failed to pick up any points at the tournament.

[38] Having stayed fit enough to start all 8 of Norway's 2019 FIFA Women's World Cup qualification matches in which the team topped a group including the Netherlands, Thorisdottir was named to the final tournament squad in May 2019.

[45] Thorisdottir got a golden retriever called Theo in 2015 and has regularly commented on the positive impact owning a dog has had on her mental health, especially during the two-year spell she had battling frequent injuries.