I'm pretty positive it was Kimeru. Almost 100%. My exact certanty is probably at 99 % . Regardless of who was the original.... Kimeru is the best! At least I think so.
And it's ok to get confused at times. We all get that way. I'm sure of it! At least one point and time.... and on occasions. But asking about something that's unknown? Well... there will always be an answer ... even if we don't know it... or haven't come acrossed it. It's a good thing to ask.
I don't consdier it cosplay. Tennimyu Muiscal (myu) of anime. They get paid for there work. Two othere anime made into musicals are Sailor Moon and Bleach.