If you allow users to choose between multiple languages, you will presumably want to customize your graphics to match the language used. If you want to keep this flexible so that you don't need to tie a new style to each language, then read on.

Create a new directory /templates/images_languagename , where 'languagename' is the name of your language file in the /languages/ directory (without the .lng). Once that directory is uploaded, the images in it will be used in place of the default images of the template set when using that language. This way you keep your language independent of your templates/styles.