Translate extension provides a “message bundle” content handler.
As an initial step towards the support of translatable modules, this ticket will adapt the “message bundle” including format validation, error messages, permissions, etc.
See task T275976: JsonContent is not safe to extend for relevant information with regards to the implementation.
It's possible to create pages with "message bundle" content format, that does basic schema validation. There is no integration with Lua modules or the translation interface yet.