Been there, done that, same speech pathologist.

She can give you all the basics, but it is up to you to practice, practice, practice until sustaining the pitch and volume is automatic, no slipping back to 'male baritone' when you are relaxed, and maintaining the singsong speech rhythm, maintaining flat or up-pitch on phrase endings rather than the male down-pitch, and sustained breath control are all key items.
If I keep all those I can sound like a ciswoman in her 60s (appropriate), but drop any of those and I won't read as female. It is particularly difficult when I have to speak for an extended period of time, as it is far too easy to slip into male didactic mode. I've run meetings with my phone on the table running SingScope, my preferred pitch and rhythm checking tool, trying to keep my voice correct.
I worked on pitch on my own for about 3 months before I started with the therapist, getting my speech consistently at around A3-C4 (roughly 180-220 Hz) I worked with her on prosody, the rhythm and intonation stuff, and got lots of homework from her passing suggestions over about a 6 week period. I did one in-office session and several additional sessions via a video linkup.
I read Aesop's Fables aloud for about 15 minutes every day. I have the Harry Potter books, and I read Hermionie's longer passages aloud, comparing them with an audiobook recording.
I figure I have several more months of this before it really becomes natural and automatic.