This was a move that had to be done. The Redskins have had a brutal off-season so far between firing their GM and losing two 1,000 yard receivers in Pierre Garcon (49ers) and DeSean Jackson (Buccaneers).
Pryor will take over as the Redskins #1 receiver after posting a 77 reception, 1,007 yard and 4 touchdown season with Cleveland in 2016. This will somewhat save Kirk Cousins value for the upcoming season, as he already doesn't want to be there and for a minute was looking at Jamison Crowder as his primary receiver.
Cousins nearly threw for 5,000 yards last season, but that's extremely unrealistic for this season. He still does have Jordan Reed but he's injury prone and is guaranteed to miss some time during the year. Cousins is a guy to probably avoid in fantasy, however Pryor will likely post another 1,000 season being the main guy for the Skins.