Andersson had a €5m release clause that expired in August, meaning Union will earn more than they had probably expected.
Celtic, Lille, Schalke and several English clubs showed interest in the 29-year-old forward.
Effzeh hope to bring in midfielder Ondrej Duda from Hertha as part of the Cordoba deal.
With the money they receive, Cologne would then look for another striker with Bochum’s Silvere Ganvoula under discussion.
Andersson’s move from Union Berlin to Cologne is now official.
— 1. FC Cologne (@fckoeln_en) September 15, 2020