Have you considered nylon? I'm not sure what the typical fabric for Chinese dragons is, but it's often used in windsocks and kites and the like, so it'll hold up to motion, is lightweight, and has a decent fluidity. Not sure about its availability in brick-and-mortar stores in specific colours, but I know Dharma Trading sells a PFD version (as well as the acid dyes to colour it with).
Therese von Ludowing (Sound Horizon's Märchen)Elsewhere: Journal ~ ACP ~ CosplayLab
Catelyn Stark (A Song of Ice and Fire / Game of Thrones)
Ichihara Yuuko - butterfly kimono (xxxHolic / Tsubasa Reservoir Chronicle)
Elisabeth - red ballgown (Elisabeth - Takarazuka version)
Thessaly (Sandman - The Kindly Ones)