I Heard Good Things…

I know of a couple of trans women who have seen her for voice training and the reports that I hear from them was good.

Helping Transgender People Find Their Voice
NPR
Heard on Weekend Edition Saturday
July 23, 2016

When they make a transition to publicly presenting themselves as a different gender, transgender people face many challenges. Possible surgeries and hormone treatments are some of them.

But one often overlooked struggle is to find a voice to fit a person's identity. People can identify men's and women's voices because there are typically different ranges in pitch and differences in timbre.

That's where Wendy Chase comes in. She's the director of the University of Connecticut Speech and Hearing Clinic. She works with people who want to make their voice sound more like their gender identity.
[…]
On why speech therapy is a good idea for transgender people
Most of our patients are seeking to allow the world to perceive them in the way that they want to be perceived. And communication is a really critical component of that perception, particularly when there is not a visual cue. And I think that it's important for there to be safe places to practice and try things out, and the speech therapy room can be one of those places.

But more importantly, we want folks to be able to change their voice in a way that is safe and doesn't do damage long-term to their vocal cords, because they're going to need it for the rest of their lives.

She is worth a try, I believe there is a nominal fee like $10 a session, she uses the workshop as a training for her students.