I’ve been doing ‘cosplay’ for years, without having a name for it.
For years, it was just ‘getting my geek on’!
There are many events, even now, where an outfit is required (well, not required, but appropriate).
I do Star Trek (I have a lot – Next Generation all divisions, DS9 Engineering and Science, First Contact Command, Picard Command and Engineering in both styles, and even Lower Decks Engineering), and also like to do some Steampunk.
And well, I do have a nice Star Lord cosplay that I like to bring out on occasion.