He was described as a multi-dimensional player possessing the ability to influence a game in a number of ways, and a bona fide future star for an NHL club.

[10] On August 6, 2020, Dubois recorded the first playoff hat-trick in Blue Jackets franchise history in a 4–3 overtime victory against the Toronto Maple Leafs.

[14] On January 23, 2021, Dubois was traded with a 2022 third-round pick to the Winnipeg Jets in exchange for Patrik Laine and Jack Roslovic.

The 2020–21 season was played in a specialized format due to the COVID-19 pandemic, with the Jets part of the all-Canadian North Division, and Dubois had to quarantine for two weeks upon arrival, limiting his training and preparation time.

The team qualified for the 2021 Stanley Cup playoffs, but after sweeping the Edmonton Oilers in the first round they were swept in turn by the Montreal Canadiens in the second.

[18] The Winnipeg Sun remarked that he "embodies everything the Jets want in their lineup and their leadership core," and looked like a possible successor to top centre Mark Scheifele, making the end of his current contract a major issue for the team.

[19] However, it was reported near the end of June that Dubois had informed the Jets that he did not intend to sign a new long-term deal, and would test free agency in 2024.

[22] On June 27, 2023, Dubois was traded by the Jets to the Los Angeles Kings in exchange for Alex Iafallo, Rasmus Kupari and Gabriel Vilardi and a 2024 second-round draft pick.

[23] After only one season of his eight-year contract with Los Angeles, Dubois was traded to the Washington Capitals on June 19, 2024, in exchange for Darcy Kuemper.

[27] On May 10, 2019, Dubois was a late inclusion to Canada's roster at the 2019 IIHF World Championship, joining the squad following the Blue Jackets' second-round defeat in the 2019 Stanley Cup playoffs.

[28] Dubois helped Canada progress through to the playoff rounds before losing the final to Team Finland on May 26, earning the silver medal.

[31] Following the Los Angeles Kings' ouster in the first round of the 2024 Stanley Cup playoffs, Dubois again joined Team Canada for the 2024 IIHF World Championship.