On my normal dose and having it stuffed in my panties all the time, it's shrunk a bit and has curved from being pulled back a lot. Libido has decreased considerably, erections are possible but difficult to achieve and maintain, no spontaneous erections, and erection from visual stimulation is nothing more than a slight twitch. Semen is slightly yellow, clear, and sometimes watery.
But when I was off my t-blocker for a month (about a year and a quarter after starting HRT), most of that changed. My size mostly returned, libido went back up, spontaneous erections and morning wood returned, erections were stronger, ejaculation more forceful though semen consistency hadn't changed much, and I was more visually stimulated. Erections were painful for a week or two though. Even before that on the odd occasion when I got rather hard, it'd be painful. I really do think it's from lack of use. During that month, the pain decreased until it went away altogether and things were more or less back to pre-HRT standards. I've been back on my t-blocker for a few months and my libido has gradually nose-dived again and all of that. I don't masturbate too often, and when I do it's not always hard, but when I got hard recently it hurt again.
Basically, I don't think HRT itself really affects it much, but rather the huge decrease in testosterone can lead to deceased libido and leads to decreased use and that's where the changes occur. Only thing HRT probably changes is semen consistency.