Oh hey Twi.
I'm assuming they get the standard regeneration/immortality/shapeshifting powers? My favorite character is Homura Akemi from Madoka Magica (respect thread for reference). I'll be using pre-Rebellion Homura for the sake of fairness.
Dio Brando: Relevant thread. I think Homura has a good chance against Dio even without vampire powers, she has much greater destructive capacity than Dio does and her timestop lasts longer. I haven't seen Jojo though, so I could be underestimating him.
John Smith/Discworld vampires: Not familiar with them, and the wiki doesn't say much about their abilities.
Edward Cullen: I'm not familiar with his abilities. Is he immune to bullets and explosives?
Alucard: If this is post-Schrodinger Alucard, Homura is screwed. Otherwise this just turns into a battle of attrition; since Alucard can keep regenerating from Homura's attacks, and Homura can keep away from him with her timestop. She'll eventually lose once she runs out of magical energy.
Blade: I think she could take him without vampire powers, timestop OP.
Marvel Dracula: Dracula can apparently bitchslap the Silver Surfer and has immortality to a ridiculous degree, I don't think Homura can succeed here unless she gets some really OP vampire powers.
Will edit some more in later (also I suggest adding Shinobu to the gauntlet).