On magic level of science.
One of usage of hormones is to be catalyst for specific reaction and AFAIK we still don't have theory for catalytic reactions so it will be done via trial and errors.
Anything with such massive changes in hormonal system will be
at best sub-human and more like other species. Cross-species pregnancy is mostly fictional idea (in reality it sometimes possible but results are sterile in most cases).
Plus there will be some side effects like increased food consumption, inhumane path of thought as gender-based hormones affect our brain too (positive for a game
), additional glands (to keep excess of man hormones in penis and female in breasts&rest) and very possible additional circulatory system with second heart
Main part of problem is reproductive system, futa without it (with just "artificial" vagina) is much much easier to make (still not without problem if you want large breasts).
Sorry for this boring real life stuff (c)