This is always hard to predict - but with news reports of so many teams looking to trade down, I was trying to game out scenarios where a team may consider trading up to acquire a particular player at #9 or #13.
Scenario 1: Joeckel, Fischer or Johnson are available at #9 to a team that values OT and expected them to be off the board.
Scenario 2: Dee Miliner is available at #9 or at #13 to a team that desperately needs secondary help
Scenario 3: No WRs have been drafted at #13 and a team wants the top WR choice
Scenario 4: Star Loutelili is the top player on a team's draft board and available at #13
I don't really see many other trade-up options. Teams usually do this to acquire a specific player who stands out and will likely be off the board by the time they pick.
Personally I think the most likely scenario is Option 3 or 4 - as WR is really a crapshoot this year, and the big DT out of Utah may be the best D-linemen in this draft.
Vaccaro and Rhodes are highly possible as well. There are a lot of team that are looking at this DB class. Really think it is more likely you see one of them then a WR. There is no AJ or CJ in this class most are very good #2 WRs do to height or lack of something you cant teach. Patterson is too raw. Allen has injury and attitude. I wouldnt take a 5'9 WR in the top 16 much less trade up for him. Which makes you ask will Hopkins or Hunter be the 1st WR maybe. I dont think there will be a yearning for anyone to trade up in this WR class.