I found that there is no plugin for automatic language detection, how to add it?
Can this function be integrated into VuePress to automatically detect the client language and jump to the corresponding multilingual site.
There is an official plugin for it, it's just incredibly hidden and also took me quite some time to find:
https://vuepress.github.io/en/plugins/redirect/
Set "locales: true" and then make sure all files are placed in a language directory inside of the docs directory. So your docs/ directory should only contain .vuepress/ and then more folders for all languages with the same structure:
/docs/.vuepress/
/docs/en/
/docs/de/
/docs/pt/
/docs/zh/
[...]