This command will switch to the specified language/localization type. If you specify the name of the language you are already using, this will reload the language file (so you do not need to restart your game if you have made changes).
switchlanguage [language name]
|Language Name||The name of the language you wish to switch to. Specify your current language to reload the language file (if you have made changes).|
If your current language is English, this would reload the English localisation file. If not, this would switch your language to English.
This command would switch your language to Russian.