The contract is not finalized, however, and the Buffalo Bills apparently remain interested in the sack artist, who's been recovering from offseason shoulder surgery.
Ansah is reportedly expected to be cleared shortly after the start of training camps, and with the compensatory pick deadline in the rearview, it was assumed the market for his services would pick up.
The 29-year-old racked up 48 sacks in six seasons with the Detroit Lions, including a 14.5-sack campaign in 2015. He missed nine games in 2018 due to his shoulder injury.
Seattle needs to boost its pass rush after trading Clark to the Kansas City Chiefs for a first-round pick, while Buffalo is looking to add another big body to its defensive line after drafting Ed Oliver with the No. 9 pick.