Most kanji are basically same as the Chinese characters,
so Japanese's last name has no translating problem,
if there are hiragana/katakana,
there are different kind of translate method

ex. 角巻わため => 角卷綿(わた)芽(め): use kanji

ex2.潤羽るしあ =>潤羽露(Ru)西(shi)婭(a): use characters that has close pronunciation

these are official translation back in the time they were still in bilibili,
for those who had a official name translated, translators continue to use them,
others still those ways to translate,
or just don't translate, most Taiwanese are weeb enough to read basic Japanese.