As in topic: is it possible to exchange torch for torch in trade window?
No, a character can only hold one torch at a time. The torch you see is what you get. Also when people change the item there are indicators of it happening. For example the accept button will grey out for a short time.
Always double check what you are trading for before you click the button. People will try to scam you. That has always been the case.
Incase you are talking about trading a torch for a torch i don’t know the answer for D2R, didn’t trade yet.