You can export your savegame via google takeout, but often these savegames will only work on the stadia builds of games, and aren't able to be loaded into stadia. (Source: https://support.cdprojektred.com/en/cyberpunk/stadia/sp-tech...)

Yes, you can download them through Google Takeout.

https://9to5google.com/2021/02/02/how-to-export-download-gam...