She's from an AU comic that Naoko Takeuchi wrote a few years after the Sailor Moon manga ended. It's called Parallel Sailor Moon and it was published in Naoko's self released Infinity Volume art book in 1999.
Thank you! I am not currently open for plush commissions but you can read the info here: [link] Currently I am revising my plush rates and I will be posting information about them when I get closer to reopening. If you are interested please join the notification list for priority wait list status when slots become available
No official color refs that I've ever seen! I was curious about Marco's art since he's the official artist for the new SM merch, but I asked him and he said his Kousagi pic was done without any input from Naoko. ;( Bummer, I was hoping it was official ;D