The deal for Donnarumma, which is reportedly worth €35 million, comes after PSG deemed him surplus to their requirements following unsuccessful contract renewal talks earlier in the summer.
This transfer marks a significant change for City, which has recently signed James Trafford, an English international goalkeeper, from Burnley.
Ederson's move to Fenerbahce is expected to be worth around €14 million, bringing an end to his long tenure with Manchester City.