In many cultures, "pants" are specifically for men or women.
In Semitic cultures (incl India), men have a specific robe-like outfit with a type of pants, as well as women having outfits with either tunics or a feminnine robe-like outfit.
In places like China and Japan, women have a specific pant-type that was traditionally for women, as well as specificly female kimono.
In places like Ireland, Scotland and Wales, men wore robes made of the tartan fabric that were long for winter, and shorter for summer that were somewhere between what the modern kilt looks like and a robe-like outfit... (ever seen Braveheart or Highlander?) and with the introduction of horses, they added tights which then gravitated to something more "pant-like".
Women kept with their traditional garb that then gravitated to something more like dresses, and then to skirts & shirts.
In Germany it was about the same with the Goths, Visigoths, drudic people etc.. then in come the Greek and Romans and our people. (we have almost as much tradition there as the Germans themselves!)
For me, I find I can't wear traditional jeans or anything. I can only "get away" with Palazzo pants (kinda like the old ones that the early film starlets wore) and be modest, but I have to wear skirts otherwise to be modest as I do have an hourglass shape.
It's hard to cover and hard to not reveal every asset I have.
I think alot of the modesty issue will stem from a woman's shape (there are many!) and how it is best to cover her shape to be modest.
For some, something akin to what the amish and mennonites wear would be perfect, but for others, it would be more of a hinderance and not covering enough.
For some, dressing 100% like the chassidim would be perfect and do a great job...
Whereas for some it would do better to modify something from the Edwardian or Victorian era to better cover.
Some ladies I know are more modest in pants than any skirt or dress due to their size and shape...
Men have it pretty easy in the respect of being modest. Just grab some pants that stay up above your hips and don't wear them too tight or too loose (not to be confused with 'tulouse'
) and a nice shirt, voila! modest!