Tim Stutzle scored, and Maximilian Franzreb made 32 saves for Germany (1-0-2-0), which will play in the qualification round on Tuesday. It went 0-for-3 on the power play after going 0-for-4 in a 4-3 loss to Team Latvia on Saturday.
Matthews, the U.S. captain, started his strong night with a cross-ice saucer pass to Werenski, who gave the Americans a 1-0 lead at 19:51 of the first period.
The U.S. kept the puck in the zone after a Germany turnover, and Matthews got it above the left face-off circle after Quinn Hughes went down the wall to keep the play alive. Matthews then found Werenski cutting down from the right point, and the Columbus Blue Jackets defenseman scored with a quick shot through the legs of Germany defenseman Moritz Seider.
The Americans outshot Germany 15-8 in the first period.
Matthews made it 2-0 with a power-play goal at 3:25 of the second period. Hughes' shot from the left circle hit Franzreb in the chest, resulting in the puck dropping down to Matthews, who swept it into the net.