A single SVG file can contain the picture texts for many languages in layers called e.g. nnn.language=ll. Displaying a particular language is a matter of its layers visibility. The [[File: syntax could contain "|language=ll" to make the relevant SVG layers visible. The daring ones could even switch the layers on automatically according to the page language (as such a name would hardly be used for anything else). The feature would probably become a standard. While waiting for renderer support of this feature, the SVG file could be passed through a simple filter.