I don't know. If I'm understanding you correctly, you don't know if Mickie and Chelsea are legit long-term players in the KOs division?
Mickie for me is a toss-up due to her veteran status. Some great superstars in the past have been able to catch lightning in a bottle later in their careers after they were seemingly done, but I don't know if I see that for Mickie unless she's willing to change her character around significantly because we've kinda see her do the country girl thing to death already. She's one of the GOATs as well, though, so can't count her out.
Chelsea is the much more likely and potentially fruitful choice though. She feels like something of a hot property right now. Despite practically never wrestling consistently on WWE TV, she's very relevant and has a lot of fans from her time there, and there's still lots of unexplored potential. I remember listening to her in podcasts and she seemed pretty dead set on resurrected the Hot Mess gimmick, though I believe she said she had some tweaks in mind for it. Either way, when you look at how Deonna left WWE without much fanfare and how she's blossomed into a cornerstone for the company (and you could say the same for Tay Conti in AEW), I think Chelsea Green is in a position to do the very same.
Tessa, in my mind, just straight up isn't happening.