Hello!

I am working on my post-apocalyptic world, Varisika, and I wanted to seek some advice from other worldbuilders. Here's a small blurb on the world itself:

"Very little is known about Varisika before the Rending, and what clues left behind by the ancients have had to be pieced together by the civilizations that rose from the fallout. However, it was the very artifacts that were recovered in the ruins left behind that allowed the civilizations to rise and flourish in the new world through the power they came to possess. Aided by the gods of Serindus, the people have retaken parts of the world, yet others remain wild and uncharted, leading to expeditions by aspiring researchers and brave adventurers to claim the glory, wealth, and fame that awaits."

I have some basic ideas of what I want each major nation to be aesthetic-wise. Examples: The Kobold/Dragonborn nation of Telke Tidre is Mesoamerican, and the Orc tribes from the Wandering Lands are being based off of Native American tribes.

I am looking for advice on how to relay the culture and aesthetic of a group while avoiding too much in the way of stereotypes. Pose me questions if it may help you, or if you're curious about something else.

Thank you all in advance.