I’m inclined to believe that the new Batwoman really is an original character by the name of Ryan, though, and I’m interested to see how Batwoman works out as the first Arrowverse superhero show centered on one hero (unlike Legends of Tomorrow) to be taken over by a wholly original character.
Interestingly, while Kate Kane’s Batwoman came with plenty of history and stories from the pages of DC Comics, Ryan Wilder is seemingly an original character created for the Arrowverse, unless “Ryan Wilder” is an alias that Batwoman is using to avoid spoiling a big reveal.