Auto-translate runs only while you are live by default, with a setting to translate when offline too
Update
Translation commands are now !trans, !trans-auto on|off and !trans-ignore <user>; auto-translate supports multiple source languages, a cooldown and an ignore list
Update
Pro channels' translation can recover Bopomofo typed with the wrong keyboard mode (e.g. ji3 -> 你)
Update
Better translation quality: Pro channels use DeepL (falling back to Google), other channels use the built-in engine, and language detection is more accurate