If you're fully disguised and make a sending, can you be recognized solely by voice? By people you know? How much do you have to have talked to make it seem like they "know" you? Generally, is it obvious who the person is making the sending, or do you need to say [DISGUISED VOICE] to "disguise the voice" to make it not instantly recognized?

You could hire someone else to make the sending if you are worried about it. Know that certain inflammatory sendings, since they would be told to Herald Jafar -before- he sends them out, really should not be made.

If people have interacted with you on a regular basis, and are very familiar with your voice, they would likely recognize it.