Updated: The reason why on average the mechs do the heavey labor and are much better at protecting ( well supposedly that is) is because the quints redesign them to better protectors by making them stronger. However, caregiver mechs and warrior femmes do exist and are not seen as an expection. There are many mechs who are much better at being nurse and many femmes who are better at being a bodyguard. Are the mechs on average stronger? Maybe. The mechs on average are suppose to be strong. I said suppose because there are many mechs who aren't good at lifting or being protectors and vice versa for femmes.
I don't think that they shouldn't be actually females or not in the way female humans are. A girl bear doesn't look different from the boar. She is just smaller that's all. Why should femmes be curvey and busty to be a female or femaleish? They can look like females in the face ( having eyelash like structure) and have female voices though. Bots ( even living robotic beings) should be genderless. However calling them an it would be insulting. The word "it" shouldn't be use for sentient, sapient, living beings like the Transformers. They can be gendered/sexed, but not in the way organics are. They were genderless, however, now it seem like bots have gender/sex, so it goes.
Both femmes and mechs should be built the same way, but femmes are
On average are smaller and/or shorter
have a rounder jaw
higher voices
However, a femme being larger and/or taller then all or most mechs do exist. Anyway, tall and/or large femmes do exist and short and/or small mechs do exist. Neither are seen as an expection. Femmes and mechs can be tall, short, small or larger. However a tall femme will still be on average overtower by a tall mech and large femme will be on average outwiden by a large mech. The same goes for the mechs. Both sexes can be curvey ( mechs will have wider shoulders though), straight, breast like structures ( flat underneath) and wide hip. Being wider does mean that the mechs are thicker. Both gender/sex can be thin or thick.
Why is the average mech bigger and/or taller? Well I was suggesting that the bots have something called proton charges to define their gender. Mechs have the positive ones and femmes have negative ones. A mech must at least have 90% or more positive charges to be consider a mech and a femme must at least have 90% negative charges to be refer to as a femme. Anyway, the positive charges is the reason why mechs are averagely bigger, taller, have square jawline and deeper voices. Wait, I'm saying that they grow, right? Well they are made up of cells ( cells made out of metal), so why can't they grow? The mechs do serve as the protectors and do the heavey labor, but femmes can be and have serve as protectors and do heavey lifting ( they done it several or many times). You assuming that the femmes take on the caregiving and easy labor, right? Well they do, but mechs can do them too. Matter of fact, they have done it several or maybe many times. Nurses mechs are not rare or seen as expection. The same goes for warrior femmes. Are mechs usually stronger? Idk. Probably so, but that's on average.
Ps. If they are genderless/sexless being that doesn't mean that they can't be genderish/sexish
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