I don't know how I feel about some of the posts equating being stupid (or whatever) to being female. I don't have any modes cause I can only be gendered female, for better or worse, but I definitely get treated like I'm stupid for having boobs and a pretty face and I'm not. Sorry for the derailment, but I think that needs to be addressed. If you have some sort of fog, which may be related to HRT, but not to being female, then one should see a doctor and not consider it part of feminization. There may be some other issue at play. My motor skills and everything else is absolutkley the same.
But as long as I'm here, if you're going to start HRT, then you will change in many ways no matter how much you think you won't. Now, you could be lucky and privileged (I am and I acknowledge that privilege) and pass 100 percent or close to it even when you dress very butch (I dressed as butch as I could today and still got called babe and baby by men) and that will probably change you for the better. Or you could not pass, be full-time and things could go awesomely or you could become very bitter.
But, if you are considering HRT, YOU WILL CHANGE. There's no way changing and turning upside down how you are viewed will not change you.