Tanev is young enough that he might still be good when the team turns the corner, so I have no problem with the team holding on to him.
However, if something really good is offered, then you consider it - essentially it would be a full re-build tanking sort of move.
Edler on the other hand is at the point age-wise that he will be too old by the time team can hope to be good again. I would pressure him to waive his NTC and move him. If he refuses, then just hardcore insult him so he changes his mind.
Maybe tell him his mother was a hamster and that his father smelt of elderberries or something in that vein. That would infuriate him to the point where he would definitely demand a trade.
Dont forget to threaten to taunt him a second time