I worked in a similar project in Appen9 but in Spanish.

I didn't receive any money since my payment cycle is due in a couple weeks, but several of my 'co-workers' were already paid in October with no issues or delays whatsoever. The only thing they told us to install was DingChat messenger app, nothing more. The WeChat pay is for chinese nationals, everybody else is paid via Payoneer.

It says "30-35 USD valid audio per hour" that honestly sounds like a fairytale lol but hey ya never know.

You'll get 5 minutes longs audio files to transcribe. With practice, you'd segment and transcribe that file in around 40 minutes. Segments marked as "Deaf" (breathing, laughs, etc) and "Noise" (non human noise) DON'T count for the "valid hour" and you'll NOT be paid for those seconds. For a more accurate estimate, you'll need to transcribe 15 audio files to make for a "valid hour". Baseline pay is kinda shit but bonuses (depends on language and locale) make up for it. YMMV.

A little advice: approve your Appen9 invoice in AppenConnect before the "expiring date" or your payment will be circled to the next month.