Currently, users have to copy/paste a trade message from the website into the game client. This is moderately easy on PC, but would be extremely difficult on console or the website.
GGG will add a Direct Whisper button(In the next few weeks). It will detect your current logged-in game session and automatically send the whisper directly from your account to the recipient. This functionality will also apply to the PC version of the trade site.
So either at or a little while after Lake of Kalandra’s release, GGG will be enabling the trade site for console users. GGG won’t turn off the existing Trade Market just yet (as the trade site for console will essentially be a beta that we want feedback on), but do plan to replace the Trade Market with this system in the near future.
This feature will both make trade easier for console players overall and will work towards the goal of having Path of Exile be identical regardless of which platform you’re playing on.
The Direct Whisper button will hopefully also be a nice convenience for players playing any version of the game.