Another example of terrible "race-swapping" is the Sci-Fi Channel version of Ursula LeGuin's Earthsea books. The books explicitly described most of the people as dark-skinned (of various shades) - the only exception were the pale-skinned barbarians from the east. But the TV-Movie turned that upside-down, making all the characters white, except one.

The TV-Movie was bad on many other levels as well. Ironically, the most engaging character was the only one left with dark skin - Dany Glover as the wizard Ogion.

LeGuin was furious. Her choice of color in characters was always deliberate:

"My color scheme was conscious and deliberate from the start. I didn’t see why everybody in science fiction had to be a honky named Bob or Joe or Bill. I didn’t see why everybody in heroic fantasy had to be white (and why all the leading women had “violet eyes”). It didn’t even make sense. Whites are a minority on Earth now—why wouldn’t they still be either a minority, or just swallowed up in the larger colored gene pool, in the future?"

But she had no real say, and couldn't even publicly complain about it until later, which she did. I recommend reading her venting.

https://slate.com/culture/2004/12/ursula-k-le-guin-on-the-tv-earthsea.html