De la Rose, 24, was originally drafted by the Montreal Canadiens in the second round (No. 34 overall) of the 2013 NHL Draft. This season, the 6-foot-3, 215-pound forward has appeared in 16 games with the Red Wings, collecting a goal and three assists.
"He's a big center / winger, Swedish player. Smart hockey player, good skater," Blues Head Coach Craig Berube said of de la Rose. "We'll see when he gets here and we'll take a look at him and see where he fits in."
Overall, de la Rose has dressed in 195 career regular-season games between the Canadiens and Red Wings, totaling 32 points (12 goals, 20 assists) and 71 penalty minutes. In addition, the Arvika, Sweden native captured a gold medal with Team Sweden at the 2018 World Championships.
Fabbri, 23, was originally drafted by the Blues in the first round (No. 21 overall) of the 2014 NHL Draft. In four seasons with the Blues, the Mississauga, Ontario native amassed 73 points (32 goals, 41 assists) and 60 penalty minutes in 164 regular-season games. Fabbri also appeared in 30 postseason games with the Blues, including 10 last season when he helped the team capture the 2019 Stanley Cup Championship.
"We wish him all the best," Berube said of Fabbri. "He's a great kid and a hard-working guy. He fell on some injuries around here and we wish him all the best."