I would like to know if the team working on Bolt.cm have plan to implement a native support for multi-language websites ? If yes when (more or less).
no, we don't and we probably won't. There are a few ways of adding multi-language support to your site.
Use the approach described here:
(please dont use hyphens and underscores in ContentType names and fields, it's a bug, but already fixed in the upcoming 3.2 release)
Use this great extension:
The reason there is no and won't be no native support is that there are many different approaches for such a functionality. Nobody can say what the best solution is because everyone would do it slightly different.