Up (or, as they'd call it, Down).

Crocodile Dundee

It's suddenly a movie about a weirdly elitist Australian talking down to a bunch of Australian expats.

In a movie where the antagonist tries and fails to hunt down and kill a flightless bird? I could see it.

Ironman

Smokey and the Bandit

Muppets Christmas Carol

Braveheart

12 Angry Men

Superman might be cool if only because it'd finally be something "different" but not "edgier".

"I'm just sayin' it's possible, ya daft cunt!"

Crocodile Dundee, all of them. Make Paul hogan the least bogan of the cast.

Star Wars

2001

"fraid I can't dollarydoo that, Dave."

Whatdya doin’, ya cunt?

Blade Runner

"Oi, ya cunt, you put Lois Lane down now!"

I think it would add a delightful extra layer of weird to Rubber.

Gone with the Wind

Like, Ma and Pa Kent still keep their origin but their son just inexplicably has an Australian accent? Maybe that's how they all sound on Krypton

Red Son but he lands in the Australian outback.

The prompt says EVERYONE is aussie

Sorcerer's Stone.

"It's leviOsa, not leviosar, you bloody cunt!"

The C Word

Frankly, my dear, I don't give a ...

No Country For Old Men

With Eric Bana playing Anton Chigur

The King's Speech.

Although the Yes movie would be good too, just so it could be renamed "Yeah Nah Yeah".

Blazing Saddles.

The first rule of fight club is you don't bloody talk about fight club!

Shrek

But keep the same voice actors

Rowling needs to fade into irrelevance

Wasn't this almost a thing? Didn't Mike Myers record almost all his lines with an Aussie accent before the last minute change? Or am I misremembering?

V for Vendetta.

My answer for these kinds of questions is honestly always just the last movie I saw, because that's always the only movie I can remember.
Well, I watched The Babadook last night and that one would be really funny if everyone were Austraian

I downvoted them because they used the americanised version, instead of the correct version that's called Philosopher's Stone.

I won't be party to allowing those yanks to rewrite history anymore. IT'S UNCONSCIONABLE! IT'S IMMORAL. IT SMELLS LIKE STINKY CHEESE!!!

Matrix.

"That's not a spoon... this is a spoon!"

I'm not sure if that movie needs another layer of weird.

The third rule of fight club, is everybody is named Bruce.

I see you've played spoony-spoony before.

Crocodile Dundee. Only Paul Hogan doesn't have an Australian accent.

"Foind your own fuckin tree ya cunt."

Any Bollywood movie :-)

What accent did you imagine him having?

I think it was a Canadian accent originally, which I assume is just his normal accent.

Captain America: Winter Soldier.

(As much for the Russian characters as the American ones)

Oi! I can't just tell yah what the matrix is mate!

The Dark Crystal.

Sweary Aussie Drama

The Last Samurai