NFL Network reported that Schneider is unsure if the 30-year-old Baldwin will return for the 2019 season. Baldwin has been trying to make it back from knee, shoulder and sports hernia surgeries this off-season.
"We know Doug's going to have a hard time," Schneider said. "There's a process we need to go through with the [league office and NFLPA]."
Baldwin has played all eight seasons of his NFL career with Seattle. Last season, he pulled in 50 catches for 618 yards with five touchdowns.
"We'll find out. We're going to deal with Doug and respect everything that's going on," Seahawks coach Pete Carroll said.
Possibly foreshadowing Baldwin's future, the Seahawks drafted Ole Miss wide receiver DK Metcalf in Friday's second round of the NFL Draft.
"He has been an extraordinary part of this program since we've been here and he has given us everything he has had, been a great competitor, player and all that," Carroll said. "We believe in him so much and trust in him so much that wherever this goes, we're going to support him forever."
Baldwin has two seasons left on his current contract. He is scheduled to make $9.25 million in 2019.