Andreasson made his professional debut for Frölunda HC during the 2017–18 season, where he appeared in one game.
[2][3] On 31 March 2022, in the first quarterfinals game of the SHL Playoffs, Andreasson recorded his first career hat-trick.
He finished the playoffs with eight goals and five assists in 13 postseason games, helping Luleå reach the SHL finals.
[5] On 16 May 2022, Andreasson signed a one-year contract with the Detroit Red Wings of the National Hockey League (NHL).
On 25 April 2023, as a pending free agent from the Red Wings, Andreasson opted to return to Sweden and sign a four-year contract with former club, Luleå HF of the SHL.