BILD says Guerreiro could be on his way from Dortmund this summer.
The Portugal international, who has a contract to 2020, is attracting interest from City and Paris Saint-Germain.
Dortmund has tried to extend their deal with Guerreiro, but the parties have failed to agree. Therefore, he is now set to be sold.
Guerreiro, 25, has scored six goals and produced six assists in 29 matches in the Bundesliga and Champions League this past season.