Update: My right nipple has become puffy, which is an indication of gyno so I'm stopping the RU treatment for now and starting Ralox and AI to get rid of the puffiness. At least I know that the RU is actually working and isn't bunk.
RU competes with Test in binding to AR receptors and the Test will eventually fail to bind to AR receptors. Test will build up to high levels in the body, which leads to high estrogen levels because Test converts to estrogen. Eventually your natural test production and estrogen levels will go back down but this could take weeks. I believe Anti androgens are similar to SARMS and will eventually shut you down if taken at high doses for a long time.
Baldness and beard growth are strongly wired to being white. Attempting to alter one's hormonal balance without feminization so far appears to be all but futile where the goal is actual regrowth.
I commend you for telling us this and not just slinking off. Your very attempts inform us more an more about what is possible but even more so perhaps about what is practical and reasonable to expect. Essentially one thing works and that is supplementation of estrogen in amounts virtually always likely to provoke gyno. I have also related how breast growth comes earlier in the process and requires far less estrogen (in fact, small titrated amounts mimic cis-female puberty) than does regrowth of hair from slick bald areas already permanently in telogen or out of cycle which might be the same thing.
Otherwise, merely using AA's might regrow a full head of hair. I am unable to find any instances where AA's did anything except halt hair loss and perhaps increase anagen without being combined with estrogen. Reductase inhibitors reduce hair loss but appear to have little to no effect on anagen cycles. Two HRT meds are commonly used to chemically castrate sexual offenders and they are cyproterone acetate which is a binding type of AA, and also medroxyprogesterone acetate which doesn't inhibit binding but rather dramatically decreases testosterone levels.
Estrogen is unlikely to work as well in a sexual offender context unless combined with such meds in the longer term. Indeed, long-term use of AA's without estrogen is unhealthy and promotes bone loss whereas the body freely accepts T, E2 either but also both. Thus the search might be for some intermediate hormonal state where T is decreased in an amount comparable to the increase in estrogen. Many, if not most receptors appear to be hospitable for either hormone as they differ little in a chemical sense although it is conjectured that different estrogen types might be less breast enhancing but AA's alone might cause serious gyno and testicular shrinkage.
AA's in some ways are even more stereotypically feminizing than is estrogen, especially related to their brutal effects on strength. AA's also are liable to completely take away sexual desire in cis-males which is a feature to me but probably a bug to most XY's. As estrogen levels increase though, sexual desire may "come back" although always attenuated and in a non-fixative process. So both T and E2 promote sexual desire but they create again, the stereotypical effects on sexual behavior all XY's fear. AA's seem the opposite to me in that they correlated with a loss of all sexual desire but then again, I only used spironolactone (and MPA). In terms of effects on genitalia, these effects seem to differ widely. XY's who are in a couple with other XY's might suffer less in terms of potency but others become flaccid and unable to penetrate. In the flaccid state, the penis may resemble one of a pre-pubescent boy and the testicles can shrink dramatically. It all appears to be reversible over time unless SRS and removal of the testicles impede masculinity permanently. I question whether MtF's can actually continue to have potency in the absence of all circulating testosterone. Most MtF's apparently never reach the hormonal profile of an adult cis-female.
@bridgeburn certainly must have reached these levels as his feminization was complete and astonishing. He continued to be able to copulate. Others simply never experience erections which can cause extreme shrinkage in length and diameter. Goddess bless.