I think it might be EASIER to teach your children equality if you are at home if you work on the presumption that women do the majority of household "stuff" (and let's work on that assumption for now)
If I was at work (I dont work you see) but ALSO doing the majority of the house stuff, that would send a very clear message to both my children that its the woman's "job" to cook and clean, and that the man gets away with not doing it. And not even because he works, because mum is working too, so it just must be women's work, mustn't it?
Whereas if I happen to be at home and not working, well of course mum does the majority of the house stuff, because she is there, whilst Dad is at work, so it makes sense for the person who is there most often to do it.
So then all you have to teach them is that in some families (more so these days than ever) the dad stays home, and in others, the mum. Sometime's its based on who wants to be at home - sometime's its based on who earns more, and both cases can be either the mum or the dad.
So no - I'm not convinced its harder, if anything its easier. All you have to teach them, really, is that you dont "have" to stay home, that if you would rather work then that is an option.
In a household where both parents are working equal hours, however, yet the woman does most the cooking and cleaning, I'd wonder how you cover that off with your kids from a fairness and equality point of view!