I've done a number of Phantom Lady sketches, pencilled, inked, and colored, and in her various costume designs, along with some tweaking of my own pertaining her image. I've sold 98% of all the Phantom Lady sketches I've ever done and posted on Ebay. Not bragging but pointing out that she's a very popular character, and I know her costume and my costume designs help a bit in that area. In fact Phantom Lady was the very first sketch I sold.
I know there is plenty of debate concerning Phantom Lady's status as a PD character.
AC Publishing actually came close to a court battle with DC pertaining the character, as they initially used Phantom Lady as their own but changed the name from the Blue Bulleteer then to Nightveil after being contacted by DC about possible copyright infringement.
However AC Publishing HAS released comics involving Phantom Lady's original stories as reprints. These I know are PD. I am certain someone can add to the topic but it is interesting in many ways, because Phantom Lady the character changed hands a few times during her "career" and there have been various derivative characters based on her through the years. I think DC should take a chill pill. Their current version is very very risque' in her costume design, not that I'm complaining!