The former Wigan and West Brom player quit the Baggies last summer on a free transfer to join the Bundesliga side. However, since his move, injury and suspension have meant that he has not played as regularly as he would have liked.
The 32-year-old's agent Valentine Hobel has confirmed that a deal is close, telling reporters: "Paul wants to show next season what he can do for HSV but for that he needs match practise and that would probably be at Sunderland."
Scharner himself stated that there is interest in him from England, and expects there to be a "concrete" offer before the end of the transfer window.
"There is yet again an interest in my services from a club in the Premiership," Scharner told the Hamburger Morgenpost.
"I expect them to put this in concrete terms in the next couple of days."
Scharner played over 200 games in the Premier League with Wigan and West Brom and scored over 20 goals in his time in England.