Need some help

I am working on my own game of thrones like universe. Using grrm formula, take a cannon event (formation of HRE), superimpose it onto an enlarged region (England) and incorporate its regional history into the main storyline (war of the roses and Marge of Anjou). Add magic at the end.

My plan (hand drawn pic related) is to take four colonizing events and superimpose them onto a butterflied Caribbean map with the Americas replacing Asia and Europe role wise. The main fixation is the Ottoman Empire, my main allegory is the story of mehmet 3 and the crusade of varna on top of the mameluk annexation, formation of janisareiws and the enstablishing the dimhiri system.

Add in the crusades with my own freaky religions happening (similar timeline of crusades with fourth storyline ongoing as a side story.) and since Caribbean, add in Native American lore and religion and history to the locals (old gods are Mayan/aztec like sacrificial) and two separate “civilizing” force that is acting in pure barbarism, and also make them locals fill the role of the Greeks to the Turks at that time, the empire that finally collapses part Byzantine part Aztec . When the back story is three rounds of Bronze Age collapse and proto-Greek diaspora which plays well into the sacrificial religion angle: the collapses are pretty fucking barbaric. North continent is Turkish homelands with a Great Lakes of northern “European” like states starting to colonize via crusade and the south has desert/semi arid steppe with an India/china/indonesia nestled way to the south (but colder).

The backstory is an Alexander like from the north once unified the coasts all the way to the gap way back when and created a pan-Macedonian identity, but adopting the aztec religion instead of convincing everyone to become Greek, that lingered in the center in a way the north moved on being conquered by Germans from the highlands in part for religious reasons, going their own feudal Germanic route leaving the center to collapse and reform three times. Each collapse saw Silk Road/indonesian city states rise around the edges of the island chain. The wars are mostly naval. When some upstarts from the south venture north and launch their own migration, gradual and slow, with a mezenkert still on everyone’s minds as this Dessen like state goes ghazi and begins expanding. Combine the crusade of varna with the fourth crusade (the one that sakes Constantinople) throw in Native American magic lore, something about soul stealing in violent deaths.

Also playing with a 4 continent option.

The real ask, what would have happened culturally, linguistically, religiously, if Islamic like (or tengri for that matter) horsey boy Turks colonized the Americas assuming a bunch of Italian cities helped threm get boats as to stop raiding them.

Any ideas, suggestions. Especially the magic. I’m thinking replace horses with something that can swim, like a man-like dog creature with kinda webbed back feet for the horsey boys, that have sentient cousins in the hills. And serpents instead of dragons, but like, giant intelligent feathered serpents. Ideas are welcome for anything fun I can run with.