Even with the launcher installed, you must connect to official Nintendo and developer servers to play.

A Cloud Version, by its very nature, does not work like a traditional game. The "Thymesia" Cloud Version on the Nintendo eShop because the game data is not stored on your Switch. It is a streaming service. Any website or torrent that claims to offer a "Thymesia Cloud Version Switch NSP Free Download" is, quite simply, offering a file that will not function as advertised.