That's not a kimono. It doesn't really resemble any kind of traditional Japanese costume.
That style is Chinese, like ancient court ladies' attire. I wouldn't be able to tell you the specific historical period it's based on though, nor how much is historical and how much might be modern or fantasy styling. So, you could start by searching for information on historical Chinese costumes worn by wealthy women, nobles, and concubines.
FF9 cosplay? Hit me up!
2014: Anime Los Angeles, Anime Conji, and whatever else falls into my lap
I now have a Tumblr
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