13 Times The Joker & Harley Quinn Inspired Wrestlers
2. Crazzy Steve
While Crazzy Steve hasn't gone on record to outright say he's been inspired by The Joker, and there are other creepy clowns out there in other media like Sweet Tooth (portrayed by Samoa Joe in the Twisted Metal television series) or Pennywise from It, it is unavoidable to draw comparisons.
The Joker is too well known as the primary example of this archetype for over 80 years not to reflect in these types of characters, as once you paint your face in white and red, smile and laugh in a sadistic way (especially in a higher-pitched voice), call yourself crazy and do things like go after your rival's kids, that's effectively The Joker's modus operandi.
Crazzy Steve even has his own Harley Quinn in a sense with Rosemary, though the two have managed to stay away from crossing the line too far into straight-up parody and trademark infringement.
Effectively, Decay is what you get when someone says they want a Joker and Harley on the roster, but to "make it your own" to avoid any serious legal problems. The inspiration is there, but more of a tip of the hat than a full carbon copy.