ほっポヨーン島。
ほっポヨヨン島でもいい。
ウルルン島は元々オノマトペ感が強い。(なんか国境付近の厄介な場所ばかり。)
It seems that DeepL translates this “厄介な場所” part to “nasty places”. It’s depressing that more and more people trust this kind of unreliable thing with little caution and think they’ve understood what is stated in languages they don’t know. (It would be “problematic” or “controversial” if I were to translate it. But fundamentally it’s impossible for the technology. Without enough world knowledge they just have to wing it. Though “nasty” is never appropriate.)
ともかく、北海道の東の方に在るポヨヨンアイランズ。