No, it is not possible to change the language. I ended up with a pen in German that is useless to me. Tiptoi's communication is not ideal in this respect, they say that their pens give access to all Tiptoi books, but they don't say that it only applies in one language each time. One might legitimately think that "all books" means ALL books in all languages. But it doesn't.

On some pens, the language of the pen can be reconfigured using the TipToi Manager software. When you try to load content in another language than the original one, the system indicates that the pen is not compatible and one of the options is to reconfigure the pen in this new language. The problem is that the pen then no longer recognises the original language. Unless someone knows how to read several languages with the same pen (not registration) without reconfiguring it again and again?

It is not possible to change the language of the pen with recording function at the moment, however it is possible to modify the stories saved on the pen to allow them to be in another language than that of the pen with the following tool: https://github.com/entropia...

Yes I did. Check out the other comments.