Skirtless_Harley
Play as Skirtless Harley Quinn. I really don't know what else to add here, it's really straightforward.  

Installation
Skirtless_Harley
1. Download
2. Extract downloaded file
3. Place the Skirtless_Harley folder into any DLC folder 
X:\Program Files (x86)\Steam\steamapps\common\Batman Arkham Knight\DLC\418930
or
X:\Program Files\Epic Games\BatmanArkhamKnight\DLC\418930
4. Run Arkham Knight 

-No Resorep required
-Harley Quinn DLC required

I owe IceMage credit for teaching me how to inject textures and hex edit properly.