Translations of SoSafe modules are grouped so that the progress on the different languages can appear together in analytics.
For custom modules, it is not yet possible to add translations in a grouped fashion. This means that you must upload the modules one at a time, without bulk upload for all languages.
Also, on the reporting side of things, each translation is shown as one module. This means that, if you have 5 modules and each of them has 2 languages, you will see 10 modules in your analytics dashboard without the option to view only language A or language B analytics.