On 18 June 2019, Hännikäinen as an impending restricted free agent agree to a one-year contract extension with the Blue Jackets.

[3] Approaching his fifth year within the Blue Jackets organization in the 2019–20 season, Hännikäinen was unable to retain his roster spot and was familiarly assigned to the Cleveland Monsters.

Having made 28 appearances with the Monsters, on 24 February 2020, Hännikäinen was traded by Blue Jackets to the Arizona Coyotes in exchange for a conditional seventh-round pick in 2020.

[4] He was assigned to AHL affiliate, the Tucson Roadrunners, adding 3 goals in 7 appearances before the season was abandoned due to the COVID-19 pandemic.

As a free agent from the Coyotes, and with the following season to be affected by the ongoing pandemic, Hännikäinen opted to remain in his native Finland by returning to original club, Jokerit of the Kontinental Hockey League (KHL), on 16 December 2020.