The Wars of Atlantis, Phil Masters, Osprey publishing, ISBN 978-1-4728-0932-2
as an OGAM (and other) setting.
You might like to get the Gurps Atlantis, which is listed as a reference. This is available through Amazon or downloadable. I'd also recommend Poul Anderson's Dancer from Atlantis (ISBN: 9780812523102) as a good insight to power-politics of the era. Just because they are “primitive”, that's not the same as “unsophisticated”.
Brief background, Posideon creates the island for a mortal just outside the straits of Hercules and sires its kings. There is no mention of Crete or the Minoans. You can imagine an enlarged Crete towed to a new position and earlier time.
A trade empire develops, with Spain, North Africa, Greece and Egypt as the main targets.
North Africa, colonists run into an expanding Indo-European horse-tribe based culture, the Amazons. First they fight, than they ally. Next is Egypt, which is being ruled by priest lords possibly non-human.
Last is Greece, where they run into city states loosely organised by Athens. Athenian and other mercenaries fought for and against Atlantis.
Lastly, the barbarians on the border are the Gorgones, who inhabit the Atlas mountain area of Africa.
If you want to know more, read the book!
Needless to say there's an uprising, led by Athens.
So in OGAM or other semi-historical game terms:
Atlantis, Posideon, troops are portrayed as Assyrian-ish, which I've got no problem with, with some later (Macedonian) influence that I'd ignore. But they do get elephants. The army is made up of chariots and chariot runners, light cavalry, heavy spear, slingers, stone throwers and javelins.
Amazons, Ares, mix of both male and female, due to Scythian style outfits, often “unisex”.
Greece, Athena, regimented ranks of Dendle armoured spearmen and chariots using lances puts this firmly in the city-state period.
Egypt, Horus, is early, I'd say Hykos as the aliens are credited with the introduction of the chariot. If you have the good sense to do 15mm, then Splintered Lights Sons of Horus are spot on.
Gorgones, Set or Hades, unless anyone can come up with an African one. These are Numidian style north African tribes rather than sub-Saharan, with some influence from the other cultures.
I would be tempted to swap the Atlantean Assyrians to Hittites and you have a good stab at the Trojan War.
Needless to say there is enough for “splinters” to remain for pulp adventurers to discover.