I have palmar-plantar hyperhidrosis and it is a stress response. Have you done any work with people who have a physical stress response(like sweating) and learned to minimize it with stress reduction techniques? I’ve considered trying meditation, because even though I can’t control my sweat glands, I have a few tricks for distracting myself when I feel my pores start to open that do actually stop the sweating from beginning sometimes, not always. That leads me to believe a higher degree of control could be attained with dedicated practice.

Edit to add: I was in a chaotic abusive household on and off from the time I was born until age 17. I’m pretty sure this happened because of things I witnessed before I was old enough to form long term memories. Onset was around age 8 or so I believe.