Ancient Rome has a much less clearly perceived look than ancient Egypt (big on eyeliner, bald heads and braided wigs) so there’s been a wide variety of makeup styles in movie depictions, given coherence (if at all) by hairstyle. This is perhaps hardly surprising since ancient Rome in the movies typically runs from Julius Caesar to the fall of the Western Empire – over 500 years: more than twice the duration of the USA to date.
Ancient Greece encompasses everything from the time of mythical demi-gods like Hercules, through the tales of Homer, through Athens and the Spartans, through Alexander the Great, to the time of the Roman Empire. The timespan and settings have allowed filmmakers the freedom to do pretty much as they please: Medea, Helen of Troy, Clytemnestra and Cassandra are characters to conjure with.