"-Vno" is an Italian suffix, "vincevano" is an Italian conjugation. You meant uīcērunt / uīcēre.
Aiming to imitate 1st c. BC Latin, I'd correct your sentence to "Itaque graecī intrāuērunt urbem orientālem et uīcērunt hostēs". It's been often observed that this Latin used "hostis" in the plural when they meant "the enemy" as in an army or a city (instead of a particular person), unlike English where the singular "enemy" can be used for both. I wonder if that was actually obeyed in other times, though...
You could play a lot with the word choice and word order, of course. "Itaque orientālem graecī introiēre urbem hostēsque uīcērunt", etc.
ēlūcet mâiōrem habēre vim ad discenda ista līberam cūriōsitātem quam meticulōsam necessitātem
It is clear that a free curiosity has a greater force in order to learn these things [languages] than a necessity based on fear. (St. Augustine, Cōnfessiōnēs I.14)