Maybe @LNDDYL knows more details on this panorama.
As far as I know on translatewiki.net, it's possible to translate messages to Chinese (Hong Kong) (zh-hk), however in recently 2~3 years, those zh-hk messages are probably ignored by Translation updater bot, therefore
# no new i18n repositories are having zh-hk.json anymore;
# the de-facto zh-hk.json on available repositories, are showing contents that prior to 2015 (or maybe 2014)
Can we please re-start translation updates for zh-hk? Or we should disable it entirely?