Dehner looks at the possibility of a trade down.
https://www.nytimes.com/athletic/6300582/2025/04/23/cincinnati-bengals-nfl-draft-trade-for-picks/
tl;dr not likely to happen in the first, but very possible in round 2. They have traded down five times (and up once) in the second in the last eight drafts. So just for kicks, I decided to look at how those trades down worked out.
In 2017, the dropped from 41 (where they could have had Dalvin Cook) to 48 where they took Mixon. So OK there. They picked up a 4th (128) for their troubles, which became WR Josh Malone, aka, who? So nothing lost, but nothing gained either.
In 2018, they dropped from 46 to 54, in return for coming up from 100 to 77. So no extra picks, just a double swap. 54 turned into Jesse Bates, so A+ there, and 77 was Sam Hubbard, another A+ who would probably not have lasted to 100. This easily has to be one of the best draft trades in Bengals history.
In 2019, they traded pick 42 for picks 52, 125 and 182. Those turned into Sample, Renell Wren and Trayveon Williams. Not horrible or anything, but nothing to light off fireworks about either.
In 2021 they coughed up 38 for 46, 122 and 139. They could have had everyone's favorite FA OL this year, Tevan Jenkins, at 38, but instead at 46 they took Jackson Carman. Insert sad trombone sound here. 122 was Tyler Shelvin (reprise sad trombone sound here) and 139 was D'Ane Smith (trombone trifecta). I would have to call that a poor trade.
Finally in 2023 they slipped from 92 to 95 and added 217. 95 became Jordan Battle and 217 was Brad Robbins. Battle has been decent and Robbins might still be here if it weren't for injury. Basically a nothingburger.
So to sum up, hands down the best trade was one that didn't actually give them any extra picks, just a higher selection in a later round. In the other five instances they picked up six extra picks and the best selection was Trayveon Williams.