(Early apologies for how terrible all of this is.)
So here we have it, a location to the far north of Breath of the Wild's map, titled Kopeeki Drifts.
seems pretty suspicious to me!
Taking a passing glance at the general shape of the map of the game and that of the Island of Mata Nui. I can say with 100% uncertainty that the Island of Mata Nui is in fact, Hyrule.
That's part one of the sooper cereal theory. Part two is that on the hidden fourth branch of the Zelda timeline Kopeke became the Hero of Time and vanquished Ganon, only to die in a seriously convenient blizzard at the hands of the Time Traveling Muaka.
Part Three comes with Ganon's revenge. We all know that Gannon has the power to change into a horrible beast when convenient for him (see the totally canon Super Smash Bros. Brawl) and this totally works for my theory because with time being common McGuffins in both lines I can also say with zero proof that Ganon and Makuta became one, and the only, TIME TRAVELING MUAKA
There you go, my definitive Breath of the Wild Timeline Theory.
But that's just a theory...