Auto backup so I can share the same app data on Bluestacks and phone

I have a Samsung Galaxy S5, running Android 6.0.1 Marshmallow. I also have BlueStacks 5. A group of games I play does not have Google Play transfer, and I thought I could use the import button on BlueStacks and find the file on my phone (save file) and copy that to the import of BlueStacks. However, seeing as every time I play on a different device, I'll have to copy through cable, import, etc. I was hoping I could set something like OneDrive to backup and sync constantly that specific file (which would get updated as saved). Currently, I have to use Android Studio to access the save file - it is hidden from the operating system. How can I do this?