Apparently the first microcomputer capable of working with the Chinese language in Chinese characters was the Microprofessor II (or MPF-II-C), a Taiwanese Apple II clone from 1982.
Now I'm 99% sure that there were early microcomputers capable of working with the Japanese language in only katakana and/or hiragana.
Unlike Chinese, Japanese can be 100% represented using only roughly 50 characters. There are actually two sets, hiragana and katakana, so about 100 total, but as a bare minimum for communication you didn't need both. Any word that can be written in kanji can also be written in kana at the cost of added ambiguity. And an utter loss of elegance.
This also means that a Japanese micro could get by with a variable-sized subset of kanji if need be. Early encoding standards required around 2,000 characters but there were surely proprietary encodings before there were standard ones.
So I'm wondering if there were any microcomputers, or addons, that allowed working with Japanese including kanji before the MPF-II-C? Perhaps there was even an MPF-II-J that was first?
I'm pretty sure Japan was more technologically advanced than Taiwan in the late '70s/early '80s, but perhaps the possibility of getting by in kana alone made it less urgent to develop a kanji-capable system sooner?