The Owls look set to snap up the talented Nacional striker by close of play today.
The Yorkshire Post meanwhile is reporting a fee closer to £2 million.
Joao is said to be on his way to England today to complete the move and become Carlos Carvalhal’s latest signing ahead of a hopeful Championship campaign.
Joao scored six goals last season, hardly eye catching. However the performances of the young attacker last season were in fact so impressive that he even earned an international call-up in March. Unfortunately he did not get on to the pitch to make his international debut for Portugal. He also has three caps for the Portuguese under-21s, scoring three goals.
The Angolan-born attacker is known to the new boss through his links to Portugal and would reinforce the striker position at Wednesday.
He would be the third player to join the Yorkshire club from Portuguese football this summer, following in the footsteps of his former Nacional team-mate Marco Matias and Braga defender Vincent Sasso.