Dadonov, who has four goals and 18 points in 50 games this season, will be an unrestricted free agent in the offseason after completing a three-year contract with a $5 million cap hit. As part of the deal, the Canadiens agreed to retain 50% of Dadonov's salary.
"Evgenii is a skilled forward that can play anywhere in our lineup," Stars general manager Jim Nill said in a statement. "Recording 20 or more goals in four of his previous five seasons, he is a proven goal-scorer at the NHL level and will bolster our offensive attack."
Although Dadonov is projected to fall short of another 20-goal season, he could generate more scoring chances for a Stars team that ranks 14th in goals per game.
Gurianov is on a one-year, $2.9 million contract and is set to be a restricted free agent. Coming into this season, he had scored at least 29 points in three straight campaigns but has only nine points in 43 games in 2022-23.
Still, the 25-year-old winger gives the Canadiens another option in an injury-laden season. Entering Sunday, the Canadiens had seven players on injured reserve and another three on long-term injured reserve, with six of those players being forwards.
The Stars entered Sunday atop the Central Division with a three-point lead over the Colorado Avalanche and Winnipeg Jets. They were also two points behind the Vegas Golden Knights for the best record in the Western Conference.
Meanwhile, the Canadiens are among a number of teams that could be in play to win the draft lottery and the chance to take presumed No. 1 pick Connor Bedard.