There will in fact be mechanics to will your title to another player so 2 players that decide to will their titles to each other in exchange could certainly do so when willing titles is implemented.
However SbS hasn't suggested that they will offer pregame mechanics for "trading" titles, and considering their stance on trading items it's likely going to be done at your own risk, and generally the official stance may be that it is unsupported so that if you will your title to another, and they decide to scam you and don't do it in return complaints don't flow uphill to SbS.
Sooo, it will be possible to do it, but we don't know if "trading" will be implemented before getting in game, but it's unlikely imo