Has anyone tried to use progesterone instead of testosterone or estrogen, in order to alleviate negative castration effects.

Progesterone is good for brain and bones. It also keeps your skin healthy to be short. Increase of progesterone levels decrease interest in sex.

It maintains your bones and keeps your brain in good condition. Should help against "brain fog".

https://en.wikipedia.org/wiki/Progesterone

I never knew this, this is actually very interesting. You mean to say that Eunuchs can use progesterone to make the negative effects of castration go away without feminization (except for the breasts)?

I did try progesterone for a while. I did not find it effective in combating the numerous issues related to low T. Also, it made me extra moody. Elevated progesterone levels in women are a significant part of PMS, and progesterone made me feel just like how PMS is described.

Mye endo told me Progesterone only works if you have Womb, Its biological effect it´s aimed to it

Progesterone is produced in about same quantity by men and women. In men it acts as a precursor to testosterone and also as an anti estrogen. It prevent the transformation of T into DHT and helps to stop hair lost. I'M not sure what it does for castrated men but most hormones are beneficials for health. I've used progesterone cream while on chem castration to reduce urination at night. I used to go 4-5 times a night and with progesterone only once. Best is to try it and see if it's beneficial for you.

I've found it absolutely amazing how profoundly my mood has been affected, probably from a combination of estradiol and progesterone. Some studies in animals show evidence of protection against neurological disorders and even repair of existing damage, although the evidence is spotty and somewhat controversial. Some past studies in humans have been compromised by using synthetic hormones that do not exactly mimic the effects of the native hormones. I'm only one person, but I haven't felt so energized and mentally sharp in years. Some part of this is the relief from having a sex drive so it's complicated.