.中国 is the country-code top-level domain for China, and has its own set of country-specific rules that they have devised.
Emoji is illegal according to the IETF IDN specification. Some naive clients allow it (i.e. don't follow the standard) but ICANN rules prohibit registries allowing registration of labels that are disallowed by the standard.
If you convert unicode to punycode it's fine? So displaying punycode TLD as unicode is fine as well? If all previous has been true then unicode being displayed as unicode can't be wrong.
Emoji is illegal according to the IETF IDN specification. Some naive clients allow it (i.e. don't follow the standard) but ICANN rules prohibit registries allowing registration of labels that are disallowed by the standard.