In the Battle of the Coral Sea in May 1942, the U.S. Navy thwarted the Japanese attempt to seize Port Moresby on the south-east coast of New Guinea. From there, Japanese planes could have ranged over the Coral Sea and supported landings on the north-east coast of Australia.
That didn’t happen; the Americans would win again at Midway a month later and bring an end to Japan’s offensive capability. Coral Sea: Defense of Australia looks at how the Imperial Japanese Navy might have proceeded in the Coral Sea following a victory in the battle of the same name and a draw at Midway, and how the Royal Navy might have responded to this threat.
Coral Sea: Defending Australia is a Campaign Study: a short book including a dozen scenarios (four operational scenarios, eight battle scenarios) in which the British Eastern Fleet defends Queensland from the Japanese. You’ll need Coral Sea and Eastern Fleet to play the scenarios.