Two problems: "In island" is incorrect in English. It is always "on the island"
The second problem is more complicated. You say "there isn't any beautiful girl," but it should be "there AREn't any beautiful girlS" or "there ARE no beautiful girlS" (both of these are correct).
In English, there are two kinds of nouns. There are count nouns which are objects that you can count with numbers. For example: three oranges, five days, two girls. These words have plural forms.
Then there are mass nouns (or non-count nouns). These are nouns, but they cannot be counted with numbers. For example: water, gold, cotton. A very important thing to notice is that mass nouns have no plural form. There are no such words as "waters," "golds," or "cottons."
This is a difficult topic. But it is important for the sentence.
For count nouns: "There ARE NO ---S"
For mass nouns: "There IS NO ---"
"There are no girls on the island"
"There is no water on the island"
so why does this have to be a mass noun? I tried to render it with count nouns as 'there is no beautiful girl on the island', just because i suspected that the sentence specifically meant this. Is this a wrong, or just weird, translation of the Turkish?
I guess it isn't wrong wrong, but that sounds mighty odd and a little dated in English. "girl" is definitely countable and it is much better to say it this way (and the way that invisibleteacup so eloquently laid out) :)
Could "hiç" be put before "kız"? Just as "bir" is sometimes put between the adjective and the noun?
can this also mean " no girls are well on the island"? as one of the meanings of guzel is 'well'?
by "not here" does that mean, when the adjective güzel is applied to a person directly, it's a physical description vs when placed with a verb or other noun ? (eg seninle konuşmak güzel, bu güzel haber)
EDIT: I got my answer. when applied to a person it is describing appearance (pretty/beautiful). for verbs and non-person nouns it means good