What sort of content? We have https://www.mediawiki.org/wiki/Extension:Translate (you may also "abuse" it by having chunks of text which are not a translation of each other).
Otherwise, you can surely use Commons as source for the craziest hacks, in particular https://commons.wikimedia.org/wiki/Template:LangSwitch does this, provided you import the related templates and create all the subpages for [[MediaWiki:Lang]].
Nemo