Trade a BOP item for another item

Hello,

Last time, I have done Naxx and i won roll on KT dagger, another rog /w me to trade him the dagger for the greatness trinket, that was a better improvement for me, i didn't accepted bc I was afraid to be tricked into something, and there is no specification about this situation in Warmane loot rules

So my question is, can we trade an item that we won on roll (ofc item that is an improvement for our gear and that we can use) for another item or money or something else ?

Tank you for your help.

There's no rules about that.
You thought it was better, then you lost a better item. You're allowed to trade it to anyone you like.