Hey! It's been a while since I debuted my Arya costume at SDCC but I figured I'd pop in and share some references and stuff because it looks like more people are cosplaying Arya, which is awesome!
To me her pants look like a faded grayish-green color, based off of this
image as well as this
one (you can see just a little bit of them underneath her paneled training skirt thing at the bottom).
My Arya pants were made of linen which I dyed, here's
a picture of my finished costume! It was a bit of a rush job and they turned out a little lighter/greener than I'd have liked, but I plan on fixing that before I wear the costume again ^^
I also wanted to take a second just to shamelessly share a photo
of my friend's Sansa cosplay, because she never posts on here, but she's awesome
Sooo excited to see everyone's GoT/ASoIaF costumes! Keep up the good work, everyone! It makes me so happy to see this series getting cosplayed!! :3