Hello,
If you are asking about Admin Console, at present time, it only supports English, it is based on ZF and you can add localization to it, if you do so, we'll be happy to receive a pull request.
KMC has several other locales but simplified Chinese is not one of them. You can look at:
http://www.panda-os.com/2014/12/kaltura-kmc-localization/
Which explains how to add additional locales. Once again, we are happy to receive contributions if you do it.
Thanks,