There’s also no other option but “None” in the game language selector.
Blueprint thing return true and it also works just fine in the production build.
But in the editor it just hangs for a fraction of a second and then nothing changes.
As far as i know, when you change culture in the editor, only changes the editor itself, (menus and panels) but not the game content.
The game content only change in the build.
You can use the Preview Game Language parameter (it’s on your screenshot) to set the culture you want and the game should launch with this culture.
A better option is to launch the game in Standalone Game mode, where the localization works and you can switch the active culture either via in-game menus or “culture=code” command in the game console (e.g. “culture=en-US” or “culture=ru-RU”).