It's dactylic tetrameter. That means that there are four feet per line, and each foot is DUM dah dah.
HIGH waving HEATHer 'neath STORmy blasts BENDing,
The feet at the ends of the lines are shorter, a few lines have extra syllables at the beginning, and a few feet are irregular, but this doesn't change the basic meter.
I think that the question exaggerates the amount of confusion over the names in Wuthering Heights. The convention of the place and period is that women took their surname from their father, and then changed it to their husband’s when they married. Emily Brontë could be certain that her readers would be familiar with this social convention.
The name Catherine ...
Heathcliff's precise ethnicity is still open to debate. In the mid-nineteenth century, the term "gypsy" could refer to a Romani individual, or it could more be used to describe someone who appears "non-English". Perhaps he is either Eastern or Southern European, or part-Indian.