Whenever the basis of the thread is "Please don't make the girl's DRK AF like the girl's DRG AF SE" and a good bit of people respond with "No that's dumb!! Armor for girls must show the belly hole because it's feminine and that's the way armor for girls should be!" I'm working to what people say. And again, armor isn't meant to look masculine or feminine, it's armor, which is meant to protect you, not show off all your curves and what not. If you want skin tight outfits that show off curves, go with a set that isn't meant to protect your body from attacks.
But seriously please, explain to me your concept of "Feminine" armor is so we can continue discussing within a slightly different context. If it's skin tight metal, which outside of that just looking ridiculous, then how is it any different than "Showing some skin", because to me it seems like it's just showing some very shiny skin if that's that case.
A practical idea of how armor works? Less metal means it's easier to cut through. Look at the first set of "Feminine" armor design you linked from.. Aion I suppose it is as someone else commented? With exception of the pauldrons, every bit of it is much thinner on the girl model than the male. Or how it purposely shows off the girl's jawline, while on the male model their face is more concealed with those (Albeit too large) additions to the helm. Looking at the second set, the men have an entire layer of metal covering their legs while the girls have skintight boots and high heels, but the two sets seem much more fair in the look intended (IE showing off the skin without pulling the zipper down to the girl's belly button while the guys have everything zipped up nicely and securely.) I have far less of an issue with the second set simply due to the fact that it's focused on a motif (Leather clad attractive badass) than I am with the first set because it's suppose to be armor, which less metal and more form fitting means it's less protective.
To bring in a game I absolutely adore and it's take on armor, Dark Souls. http://i.imgur.com/U3Mgz.jpg (Ignoring the clipping issues, as it's just how games are) This is an armor set in the game (Coincidentally worn by arguably the most powerful character in the game) It's purpose? To protect the person wearing it, as armor ought to be. Now, that's not to say I'm saying "Every set ought to look super bland and boring and only make 150% sense!", because this is fantasy after all. What I am saying is that whenever sets have ridiculous things added or remove more sensible things, it should be the case for whatever model you use in the game.
So again, armor isn't meant to be "masculine" or "feminine" it's suppose to provide the most protection to your body. In fantasy, feel free to do whatever ridiculous thing you want to it, but if it's going to make sense on the male model (Or make little sense on the girls model) it ought to be equal for both sides.