Google has announced that Red Dead Redemption 2 will come to its Stadia platform on it November 2019 launch. The wildly popular Rockstar game will thus be available for streaming via the new service from its very first day. At present, it is not clear if this title will allow saving across platforms.
https://www.notebookcheck.net/Red-Dead-Redemption-2-will-be-a-Stadia-title-on-launch.436926.0.html