They might have been able too take away US presence in the Pacific in total by sinking the Enterprise and Hornet and invade Hawaii.
Japan could never, repeat never, control the Pacific uncontested. Invasion of Hawaii was a Yamamoto opium dream. Victory at Coral Sea might have led Nimitz or King to move USN forces, especially subs, back to Pearl, which has very beneficial effects on the commerce war, bringing Japan closer to defeat much sooner...
Forget Australia then, for them its over.
Australia was never under serious threat.
Next to that, the US mainland is at stake.
Only if Japan signs an alliance with the Romulans.
All of new Guinea would have been occupied, as well as the Solomons and maybe even new caledonia and Fiji.
Possible, presuming Yamamoto doesn't demand Op MI anyhow. If he does, the balance is redressed in an afternoon.
No way for the allies to take them back untill the Japanese fleet was destroyed.
Really, really not. USN would have more carriers than Japan going into November '43. Stronger Japan in SWPA is liable to encourage a one-road CPac strategy, rather than the wasteful 2: Tarawa, Saipan, Oki. Presuming subs all in Pearl, these 2 factors could end the war by the end of '44.
who knows how the Japanese are faring in Burma and China. if they won that, they might actually have won the war overall.
LOL. Burma & China were enormous traps for IJA forces. (Allies, too, unfortunately...)
they would enter the USA and reach all the way, to my guess, Dallas before being stopped.
ROTFLMAO. I haven't heard anything so funny since a Cardinal told Buddy Hackett, "Absconde obeseri illegitimo."
Japan is bombed into submission by 1946.
I broadly agree, except the change in priorities, as noted, is liable to mean it wouldn't even take as long as OTL.
And this assumes that America does not even go back on Germany first as a temporary measure.
It didn't happen after Pearl Harbor; I see no reason it would TTL. A loss does have interesting knock-ons for ETO, tho. Presume 1-road PTO, a) more shipping is available to move troops (less tied up in PTO, not least 'cause it's not swinging at anchor waiting to be loaded/unloaded & b) more LC are available for ETO, so 1.) more 'phib ops can go in Italy (presuming the lunatic mainland campaign goes ahead

) & 2.) Anvil can go simultaneous with Neptune. This likely means no Bomb used on Japan...which (as I've said often elsewhere here; are you tired of hearing it yet?

) may mean nuclear war in the '50s...
Getting the aircraft carriers around Guadalcanal could mean that the Japanese would deny US vessels from approaching the area. Thus they could pound and bomb Henderson field and move more troops in by troop transporters, rather than the Tokyo Express. With more preparatory bombardment, better air surveillance with carrier borne aircraft and secure seaways, the US may find it difficult to resupply the Marines in Guadalcanal.
True. However, it presumes Japan believes there are more Americans in Guad, which she didn't. And honestly, more IJA in Guad was a bigger problem for Japan than for the U.S.; she could scarcely maintain the forces she did send.
3) They'd have to occupy Port Moresby, which would be a huge PITA and almost certainly more trouble than it was worth. All supply would have to come around the long tail of New Guinea, where it would be ridiculously vulnerable to Allied air, submarine and surface attacks.
I never thought of that.

Y'know, that's a really good argument for keeping subs in Oz. It'd inflict severe attrition on IJAAF, too: even relatively minor battle damage & lack of spares took aircraft right out of action. (IJA didn't seem able to cannibalize parts, if
Fire in the Sky is right.) More pressure on logistics means more opportunities for everybody's subs...not to mention 5h AF.