'Arabs' is not an implied noun; the word really is a noun.
And even if we imply another word such as 'people' what we will have is a noun adjective rather than a possessive. So 'Arab people' is possible (though 'Arabic people' is better), but I'm afraid you still do not have a possessive.
The only way to get this in the context you are looking for is to have a country and to suggest that its people have talent. If you simply want to say that the people have talent you must do this do this without a possessive.
If you must use a possessive, you need to lose the verb - as in 'Arabs' talent' but the moment you add a verb you have a construction which is a basic statement with no need of a possessive.