Eh. Betty Noir is a cool name. And I really don't think reusing it (or any other) should necessarily count as plagiarism. Just look at all the different Cat-Mans, Scarecrows, Scorpions, Black Cats and, well, Redwings that have appeared in comics over the past few decades.
(Then again, Catman is probably a bad example, since DC pretty much lifted both the costume and the name from the original Golden Age version)