https://www.gamespot.com/articles/no-cloud-saves-after-all-for-nintendo-switch-games/1100-6461634/

Nintendo Switch's online service has been much anticipated, and despite previous delays its release is right around the corner. Now, it looks like one of its biggest selling features (especially if you've ever lost or broken your Switch) won't be available for all games; some big titles, like Pokemon, Let's Go Pikachu!/Eevee and Splatoon 2, won't allow cloud saves.

As reported by Game Informer, a message saying "This game does not support Save Data Cloud backup" has begun appearing on many Eshop pages. This includes the upcoming Pokemon and Splatoon, but also Dark Souls Remastered, Dead Cells, FIFA 19, and NBA 2K19. Nintendo has said in the past that not all games would support cloud saves. Other games, like Mario Kart 8 Deluxe, Mario Tennis Aces, and other games that will use the service's multiplayer capabilities, don't have the warning.