The "replacement" refers to replacing hormones you don't naturally have with them from some external source, not blocking some sort of existing hormones. If you have estrogen when you hit menopause, it's still called HRT.
Anti Androgens are not dangerous. If you have no primary sex hormone for an extended length of time, you get osteoporosis, sure. But to imply that somehow taking estrogen is safe compared to that is silly. |
But whether or not you can call something HRT is irrelevant, what matters is if it's safe.
Now, I know that local application of estrogenic creams to the breast area does have localised effects, so I'd imagine the effects would also be reasonably localised in the case of genitals, but don't quote me.