The postings don't state a standard working day for transcription, so I can't give you an average. None of the roles here sets daily hours. Most are remote and the pay is quoted per hour or per audio hour, not per day.
What the postings do show is how the work is measured. The Babel Audio roles pay up to $110 per audio hour, meaning per hour of audio you transcribe, not per hour you spend working. Transcribing takes much longer than the recording runs, so your earnings per hour worked will be lower than that figure. The micro1 roles are paid by the hour worked, at $10–$22/hr on the ones shown.
The Babel Audio postings mention keeping one tagging style "across many hours" of audio, so expect long, focused sessions. Whether you can pick your own hours is decided by each platform, so check it before you apply.