Prior to the trade deadline, the Jets dangled Sheldon Richardson to interested teams. Ultimately, they didn’t find the level of interest they anticipated and Richardson remains in green and white. Two GMs tell Jason Cole of Bleacher Report (video link) that they expect much of the same this offseason when/if the Jets seek out trades for Richardson. 
[RELATED: Richardson Says He’s The “Odd Man Out”]
No one denies Richardson’s talent, but his off-the-field troubles are worrisome to teams, including the Cowboys who explored a deal for him earlier this week. Furthermore, Richardson is slated to hit the open market after the 2017 season and teams will only give up so much for a player that could amount to a one-year rental.
Another thing to keep in mind is that teams are generally more desperate for help at the trade deadline than they are during the offseason, when there are more options. If the Jets were unable to work out a deal for Richardson now, one has to wonder if the market could actually be weaker in the early spring. At the same time, if Richardson stays out of trouble and performs at a high level in the second half, it’s possible that his stock could be boosted.
You say that teams are more desperate for help at the trade deadline than they are in the offseason, so in trading a star player like Richardson, the Jets would get less during the offseason.
I disagree.
A player coming to a new team in the middle of the season has to get used to new coaches and a new system, learn a new playbook, establish chemistry with new teammates, and get used to new surroundings. That all takes time, so a new player coming in at midseason might not actually be effective for his new team til the last quarter of the year.
It’s a different story in the offseason, as a new player has OTAs, training camp, and preseason to learn and can start the season very comfortable in his new surroundings.
In season trades are very difficult in the NFL, and they are not the best way to either trade or acquire upper echelon players.