In the gamepass version of the game, there are no saves along this path. \AppData\Local\AtomicHeart\Saved Hence the question where are the gamepass\msstore saves and whether they can be transferred to the steam version.
Topic on Talk:Atomic Heart
The location of the save data in the gamepass version is %LOCALAPPDATA%\Packages\FocusHomeInteractiveSA.579645D26CFD_4hny5m903y3g0\SystemAppData\wgs\<user-id>
In each randomly named folder, there is a file with no extension, so if you name the file something like 0.sav, 1.sav, it might work for the Steam version.