I saw someone in the community saying that VAMX can import language packs, is that true? I want to know how to change the language to Chinese

It's not possible to change the user interface language of VaMX.  It is possible for the female to speak a limited amount of dialog from a few different languages. As you interact with her she will moan and say sexy lines in the voice, accent, or language chosen in Sound -> Female Voices and languages . These languages include French, Spanish, Japanese, Russian, and also there are accents like Scottish, or Android, Anime, etc.  There is a possibility to separately pay for AI Chat, which can be in any language, but this costs us a huge amount per month/user/question asked so it's a separate subscription that can be used with VaMX, but it's not part of VaMX.  It also doesn't effect the UI.  It does let you use NSFW chat (like a NSFW ChatGPT, or ChatGPT itself) in almost any language, by speaking to, and hearing a response.  This is a separate feature that can be added on, and is not included in VaMX.