Pretty much everyone on the internet has armchair diagnosed
Trisha Paytas as being a walking HPD stereotype. Look how she flip flops all over the place, says literally anything to get attention no matter how bad it makes her look, films everything possible about her life and uploads a billion times a day. Chloe is far more calculating, sticks with one overarching story (despite some discrepancies), films nothing about her regular life, and has proven she can go for at least two days at a time before having to get back on the internet.
For Trish, any attention is good attention, she doesn't care about her image at all. She shakes off scandals by moving so fast that it just confuses and overwhelms the crap out of everyone while she just trusts that she will maneuver her way out of it in real time. Talk about living life with the brakes off. Meanwhile, Chloe wants positive attention only, she wants to come out of this with a pristine reputation, and she is not handling her first scandal the way Trish does for sure.
Trish fights any random hater with glee, coming for them claws out. Chloe deletes most of them to pretend they don't exist, and selects a few high profile ones to pay attention to so she can play the victim-trying-to-protect-others card. Trish has come out and defended people prematurely before everyone's receipts were posted, and she came out looking worse for it. Chloe waited until she knew how everyone else was going to play it before making her move. She mentions new stuff came to light since Nan's apology--afaik nothing substantially different actually has arisen since, just more of the same. She just said that because she'd been seen making positive comments on Nan's video and had to protect herself.
I get that HPD is probably a spectrum and Trish is at the high end, but their behaviours just seems so fucking different. So I think Chloe is a narc. Whether she's a vulnerable narc or swings from grandiose to vulnerable, idk. The victim actions point to vulnerable but the cult she's created says grandiose. That said I'll change my mind about HPD if we ever get a video of Chloe crying on her kitchen floor or making a song about cheerleading with Jesus.
Meanwhile I can't wait for the day she explodes with narcissistic rage, or as I believe the cool kids say, chimp out. She has promoted herself as a medical educator when she knows nothing just for her own ego and to make her condition seem legit, lies about her academic sources, given out shit advice, and has encouraged hundreds if not thousands of impressionable, vulnerable people, to fake symptoms of illnesses they don't have, covering up the ones they do, and thus not get the treatment they need. Long or short, I hope her fall from grace is memorable.
TL;DR: Chloe has diagnosed herself as many different sentient beings but on the other hand, Trisha once self-identified as a chicken nugget. EDIT: when I find the link I"ll put it here.