In the Store page https://www.gog.com/game/xiii it is write AUDIO AND TEXTE for english, francais, deutsch, espagnol and italiano !!!

in GalaxyGOG it'is write :
Update (04 October 2019)
We have added full support (audio & text) for the following languages:
French, German, Italian, Spanish
NOTICE: in order to play the game with your preferred language's audio & text, please start a new game. While it is possible to finish your current playthrough in the language of your choice, please be aware that only the text will change while the voices will be in English.

What ? just texte and no audio ?...

but in reality i have just english texte and audio..., no menu to change (in game, and in downloader)....

May you help me ?

EDIT : ok i have found, you need to instal it with galaxy, after it you need to go on "gérer installation" and "configurer", here you change the language, after that you need to up-date-check file to play in your chosen language (video and text, not the ambiant-sound)

But now, why i can't download an offline installer in other language of english, and i need galaxy for play in other ???

You have to edit the following 2 settings:

1) In XIII\System\XIII.ini (subtitles)
Under the section
Engine.Engine

Set
Language
to one of the following: det, est, frt, int, itt

2) In XIII\System\DefUser.ini (voices)
Under the section
HXAudio.HXAudioSubsystem

Set
SoundLanguage
to English, French, German, Italian, Spanish

Beware that the DefUser.ini is a template file for the game profiles in XIII\Save\*.pro, so the voice language has to be applied before playing or you have to start over with a new profile.