When Daniel prophesied about "Grecia", the Greek peninsula yet consisted of individual city states: Corinth, Athens, Sparta, for example. Greece did not become unified fully until the Persian wars, about 80 years after Daniel prophesied about that war.
This prophecy was definitely fulfilled in the time of Alexander the Great.
Now, will it be fulfilled again? Perhaps! What has happened before will happen again.
In that case, I see no plausible interpretation that "Grecia" would refer to any other nation than Greece.