If all it takes to be an Edgelord is a black and red color scheme and some capacity for stabbiness, every one of my Thorn Wielders instantly qualifies. And that's before we even get to the "Yeah. Technically dead, body-snatching ghosts"-bit. 😝
And that's really where my skepticism about the term comes in. The 'Edgelord Checklist' always seems to include details that are so general and so common to characters both good AND bad that they could apply to darn near anyone. I mean, is Kai an Edgelord character? She's an orphan, a Death Mage's apprentice and she nearly got sacrificed to a demon when she was four. (I'd call her more of a Nerd Girl, myself, BUT... by some of the definitions in play? Yep. She'd get pegged as Edgy. Even if she isn't prone to wearing black or talking about the gory details of soul magic and the howling oblivion of the Void in anything but very academic terms.)
I just don't see a lot of use for a term that's potentially THAT broad...