Methot has spent the past five seasons with the Ottawa Senators, having spent much of his time alongside Erik Karlsson on the team’s first pairing.
The 32-year-old is not known for his offensive capabilities, having totalled 21 goals and 120 points in 579 career NHL games.
“We are thrilled to have the opportunity to acquire a player of Marc’s calibre,” Stars general manager Jim Nill said in a release. “He has proven to be a capable and steady defenceman that can play well with an offensive-minded partner, and he will add a tremendous amount of leadership and experience to our blue line.”
He’s represented Canada at the world championships twice, finishing fifth both times.
The Golden Knights selected Methot in the NHL Expansion Draft on June 21.
The Ottawa native has two years remaining on a contract that carries a $4.9-million cap hit.
Ferguson was drafted by Dallas in the seventh round — 194th overall — of the 2017 NHL Draft.
The 18-year-old had a 2.74 goals-against average and .922 save percentage in 31 games with the WHL’s Kamloops Blazers.
Dallas was looking to upgrade its blue line after missing the post-season a year after finishing with the best record in the Western Conference.
Nill had already bolstered the team’s netminding situation with the acquisition and subsequent signing of Ben Bishop, and Methot will join a D-corps that includes John Klingberg, Dan Hamhuis, and Esa Lindell.