https://www.cbssports.com/nfl/draft/news/2018-nfl-mock-draft-jets-trade-up-for-sam-darnold-christian-kirk-lands-with-patriots/
They have Josh Rosen going #2 to the Giants. Here's what they have the Bills doing:
21. Buffalo Bills
Mason Rudolph, QB, Oklahoma State. The Bills will likely explore a variety of trade-up options. Ultimately, the price will be too steep to move around 20 spots in this draft to pick a quarterback. They stay put, pick Rudolph and start to build around him with their glut of early-round picks.
22. Buffalo Bills from Chiefs
James Washington, WR, Oklahoma State. If you pick Rudolph, why not pair him with his ultra-productive downfield wideout? Washington has outstanding ball skills, body control, and some of the most electric deep speed in the class.
With consecutive picks, grabbing a QB and WR who already have chemistry and were mega-productive sounds like a very good idea to me. Note that I have not done extensive research or anything but this does sound like a good scenario.