The Winds are based on pretty universal things. There are some cultural differences between, say, the Empire's conception of a Chamon-wielder and that most common in Ind, but fire is still fire wherever it is and it's rarely going to be hard to see the underlying logic even in a completely alien take on it. But magic based on liminal boundaries is inherently extremely variable. The primary boundary in Nordland and Ostland is the boundary between mostly safe pockets of civilization and the very not Forest of Shadows. But right next door in Middenland, where most of the forest is much safer and society is much more monolithic, the primary boundary is that between cultural insider and cultural outsider. In Wissenland, the province of factories and industry and universities, the boundary is between ignorance and knowledge, between skilled and unskilled, between educated and not. In Averland, a mostly-flat, mostly-unforested province full of pastures, you reach the boundary when you can see forever in every direction and still see nothing. Where and what would the Hedge be in Altdorf? In Karak Eight Peaks? In Kislev or Bretonnia or Araby? And how do you make an institution, a culture, and a curriculum that works with people from all of them?