Left-footed Hysen, 25, will most likely move to Gothenburg for around £950,000.
"People probably think I'm stupid, but I have thought this through", he told SPORT-Expressen.
"I am in England now and I have met with Sunderland representatives, but I cannot comment on the negotiations at the moment.
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"I have told Sunderland that I wish to go home [but] it is not something I decided on recently: I have thought about it for a while now.
"I will be a father in January and England is not the right place for us as a family."
Hysen added that he will cherish his time in the north east.
"It's been great to play in England and I am still as energetic and ambitious as before," he said. "I will not calm down in any way."
Gothenburg sporting director Hakan Mild said of the situation: "Obviously we are hoping for a quick solution."
Winger Hysen - son of former Liverpool defender Glenn - scored four times in 26 appearances for Sunderland but Scotland youngster Ross Wallace was often preferred to the former Hacken and Djurgardens man.
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