I’m afraid fake, fraud, con, counterfeit are not for PERSON. They can be used as verbs, nouns or adjectives but the nouns indicate the thing, not the person.
But con artist, faker and counterfeiter r relevant. As i know, in American English “faker” is often used for the one who cheats others by selling bad quality jewellery at high price (more than it should be).
Anyway thanks for “quack” and “charlatan” which i have put inside my head after reading ur post.