They actually tried her animated series outfit, it's really about what looks good on film and of course David Ayers's style, studded belts and such. Besides, Hollywood doesn't like masks, because people will go to the movies to see their favorite actor's mug on screen
Wasn't the story that the actress just didn't like the real outfit ?
That she was the one who preferred to wear that dumb t-shirt and those stupid looking high heeled shoe/boots?
Well at least most of her depictions in the comics for now have her with blonde pigtails with blue and link tips so we can at least somewhat recognize the character....
-J.