Is it permissible for a girl to create a YouTube channel using only her voice, after altering the pitch of her voice, given that a woman’s voice is considered 'awrah (something that must be concealed)?

It is permissible for you to create the channel if it contains a significant benefit, and you will be rewarded for it, Allah willing, provided that you do not speak alluringly and that your voice does not cause temptation, because the preponderant opinion is that the woman's voice is not in itself 'awrah (private/concealable).