My guess is it will be be just a steam release of the
Windows store version of the game (i.e the switch / ps4 / xbox release). I've not used the windows store version (if anyone has saves please send em my way) but the switch version uses a new name for the pc saves instead of being saveXX.ff7 its now ff7savexx. I have heard (but i don't have it to confirm) that the windows store version uses some kinda of hash for the save file names. They are also no longer saved in the FF7 installDir but instead in AppData. I would suspect they could easily make a way to covert them if they wanted to. Im sure it will take me longer to figure out how they generate the save name hashes than any real "converting" of save data.
My guess of what the new version will contain
- 3x speed modifier and other baked in cheats that are on the switch version
- Removal of the SE account needed for cloud sync
- Use of the save naming convention and paths from from the Window PC release
- Japanese Text support out of the box
IIRC you can use most mods on the switch version (the only of the new ones i own). the limiting thing being what their baked in driver supports since we don't have a ffnx built for switch. Someone out here has to have the windows store version to tell us about modding it. I suspect for windows its mostly the same as this upcoming release.