The 32-year-old forward joined Sheffield Wednesday on a free transfer from Middlesbrough in the summer of 2021.
Last season, Johnson featured 44 times for the Owls and helped them earn promotion to the Championship.
Johnson has fallen down the pecking order under new boss Xisco Munoz and Derby County are interested in him.
Sheffield Wednesday are open to letting Johnson leave Hillsborough this summer if the right bid arrives.
Derby, who have started the season in a rocky manner, opened negotiations with the Owls.
But it has been claimed that a move to Pride Park is not in the cards for Johnson due to cost-related issues.
Johnson has yet to feature in a game for the Owls this season and it remains to be seen whether he will be able to seal an exit before the window ends.
