Provide a mechanism for localisation. Ideally cocostudio should allow a preview view for all localisations.
The language (localisation parameter) should be passed when the UI/Scene is loaded in the game. (The alternative is to support localisation in cocos2d-x (e.g. a global parameter that is automatically set when a cocos2d-x application is started)
1st priority: string localisation: strings are defined in a key-value file. Key binding is used in the UI file. It could still be possible to hard code strings in the UI.
2nd priority: image localisation. Support different image assets depending on the used language.
Please contact me in case of questions as I have a lot of experience in the domain of localisation.