I was given a task to add Chinese language to the EPiServer website (v.10.10.4.0) In the Manage Website Languages view in admin mode I found among many variations "zh" language code. I'm not really sure is it Chinese traditional or simplified, because these two also appear on this list or maybe it is some other version of Chinese language? From my understanding, a common choice is the Chinese simplified (zh-hans) or maybe in EPiServer, I should just choose this "zh" language as a default choice for the Chinese version of the website?
Hi, late answer but you should be looking to .Net framework CultureInfo.
zh is neutral culture (it has no country) but so are the zh-Hans (simplified) and zh-Hant (traditional) see the note under this title (the second note): https://docs.microsoft.com/en-us/dotnet/api/system.globalization.cultureinfo?view=netframework-4.7.2#culture-names-and-identifiers
But, then there are the specific cultureinfos for like chinese in Taiwan, China mainland, Honk Kong, Singapore, Macao. And when the country is attached to the language formatting etc changes accordingly.
So I guess the answer to your question is, you should choose the language that you are supposed to support. Same differences as there are for en-UK and en-US (formatting differences, pound vs dollar, etc).