Academic standard transliteration of ё is e (Gorbachev, Khrushchev, Potemkin.... Alla Pugacheva).Originally Posted by Leof
In more everyday transliteration I'd just stick to "yo" in all cases. But obviously you can do the whole "io" after a consonant thing, if you want.
Чё as Cho is more a phonetic rendering (transcription) rather than a transliteration, as you are not preserving the original spelling and instead focusing on pronunciation.