A first edition of "Wuthering Heights" is shown as being attributed to Emily Brontë. It was originally published under the pen name Ellis Bell and only appeared under her real name after her death.
Several characters mispronounce the name Bronte as "bron-tay", as if it were French. It was actually pronounced "brontee". The father was Irish and originally named Brunty, but he changed the spelling.
There is a scene where Emily and her family are all taking a photograph together, where a camera on a mount with a traditional curtain is shown. However, the first cameras were not available until the daguerreotype was released to the public for the first time in 1839. The movie takes place entirely in the 1830s, when the invention was still being constructed.
Right at the beginning of the film, one of Emily's sisters uses the word "sofa" when Emily falls ill. As it was Victorian England, the word would have been "settee."
While they're on the moors together, Branwell suggests to Emily while they shout "Freedom in thought!" that she should "give it some wellie." This is most likely an anachronism, as there are no records of this term being used in the mid-19th century.
There are few, if any, literary references to the term before the late 1970s, at which time it became popular as a slang term.
When Emily tells Branwell what she thought of his writing, she uses the term "off your head" (on drugs). This is clearly a modern day term that would never have been used in 1840s England.