The phrase "a freak for" is correct and usable in written English.
It is typically used to express a strong enthusiasm or obsession for something.
Example: "She is a freak for vintage fashion, always hunting for unique pieces at thrift stores."
Alternatives: "crazy about" or "obsessed with".
I'm just a freak for the Balmain and Balenciaga".
"I'm a freak for sexy, sleazy, tacky, beautfiul design from the '70s," she says.
Steven A. Ballmer, the C.E.O. of Microsoft, is a freak for numbers.
She remembers classmates thinking she was "a freak for reading [Soviet writer Maxim] Gorky".
Anybody who feels like a freak, for whatever reason, can really find a role model in Divine.
Even in the company of the keeper of the vault, being a freak for the Fox was a lonely business.
He went on to be a pariah in high school, an art school flunky, a dismal performance artist, a speed freak for a turn, then one of the untold zillions who move to New York, looking to make good on their vainglory, only to end up stuck in the menial labor force.
It's not like writing fiction – you have to be less of a control freak for a start – but it's ultimately quite liberating.
But you may have a control freak for an adviser who lives by the motto "My way or the highway" and doesn't believe your results.
The downside: Mr. Collier, whose Kennel Club cronies affectionately call him a bit of a control freak for tweaking every last detail of the show, has to steer clear of the premises and remain ignorant of the seven finalists, per his own rules, until summoned for the big pick.
He was, admittedly, beaten by Claus Jensen's speculative long shot but that was almost a freak occurrence for Charlton, whose overall play was disappointing and who were two goals down at that stage anyway.
