Recently it became known that despite the backward compatibility, it seems that it will not be possible to transfer the preservation of the same game from PlayStation 4 to PlayStation 5.
The assumption was based on official data about two games: Marvel’s Spider-Man: Remastered and Yakuza: Like a Dragon. The developers of these games have confirmed that it is impossible to transfer the save data from PS4 to PS5.
It was assumed that, in general, this is possible through the cloud service using a subscription PlayStation Plus. We don’t know what it is yet, but it is still possible.
One of the developers of Insomniac, which plays Spider-Man: Miles Morales, answered the question on Twitter in the affirmative.
Unfortunately, he did not explain how it would be implemented, but now the main thing is that it is even possible. From all this we can conclude that everything will depend on the specific game. We can suppose that the migration of saves will be available for games that are initially developed primarily for PS5, but are also available for PS4.