Like a Dragon: Pirate Yakuza in Hawaii actually leaked months ago, but it was so ridiculous nobody believed it was real
Except, of course, it all turned out to be true, from Majima's starring role to the fact that there's a swashbuckling fighting style. The leak even claimed that the "central areas include reusing Hawaii, the 'Madlantis' island, and new hub area that acts as a base." That's a level of specificity that's impossible to put up to pure coincidence.