One thing Zero-K actually does lack is Asian language unicode support, which is the reason I didn't keep translating any of the game into Japanese.
Language support for playability > comms
Spring actually natively supports unicode - this is how we have Russian, for example.
However, it fails to render CJK fonts on windows because the library used for font rendering does not by default generate a cache of substitution fonts, and the fonts used in the game need font substitution because they don't have any CJK characters natively. Additionally, Spring does not tell the font library to generate the cache because that's a fairly long process.
This works fine on Linux.
If you possess a windows operating system with some CJK fonts installed, then you can help by verifying whether launching spring.exe with the --gen-fontconfig command line option helps to resolve that issue, and if it doesn't, then trying different things until it does.
You can check whether CJK fonts succeed to render by pasting some CJK characters into lobby chat.
Namely, this is the second subtask of ZK:3119