Is a touchy subject. I'm not as universally adverse to it as many of my fellow SJWs. I believe re-imagining stories in a different setting is a powerful tool. Both in terms of time and culture.
It's more a problem I feel when the Hollywood version is the first and possibly only Live Action take something will get. Which is common since the most ambitious Anime are simply not do able on the budget limitations the Japanese film industry has.
But with Death Note there was a live action version made in Japan, that did pretty well. So I have no problem with Hollywood setting it's film in America. I do tend to agree that Westernizing Ghost in The Shell isn't a good idea (and it gets worse) (But there is an opposing view) (and another). As far as Pokemon which there has been buzz of a Live Action version recently, my thoughts on that are pretty complicated. Four of the 6 (is it 7 already) regions are based on Japan, but one is also New York and Kalos is France.
The most offensive thing about doing a Western Re-imagining to many is the White-Washing. We want more diversity in Nerdy Hollywood movies in general, even when the source material isn't foreign.
Hollywood has made a lot of progress in being willing to cast more diverse films. The Force Awakens shows that a diverse cast certainly won't hurt an established Brand.
The issue with Adapting Anime is a paranoia that America can't handle something with no White Men. (Even TFA had Han and British villains to fall back on, and most of the female characters are still White.) So they cast a bunch of white characters until at some point they notice there are no roles for Asians left.
Why not focus on adapting some of the Animes that are diverse already in the original source material?
Code Geass absolutely allows you to have a lot of young white leads and stereotypical British Villains. But because condemning Racism and Imperialism are largely what it's all about none of us SJWs would complain, as long as Suzaku and the other "11s" are Japanese actors, and Kallen is still mixed.
Attack on Titan is so overwhelmingly White it would probably be called Racist if it weren't a foreign work. In fact the Western equivalent of it would be a dystopic future where there are no White people left but one half Breed who happens to be the most awesome character in the story. I could see David Duke writing that actually.
But I think the best choice would be Gundam 00. It is still the only Gundam series I'm familiar with, maybe others are equally diverse, I don't know.
The main Messianic Archetype lead, Setsuna, is a thinly veiled Kurd, one of the most obscure and minor minorities of all. And surrounding his story-line are other Middle Easterners like Persians and Arabs.
Saji and his sister were the Japanese entry point characters. And it has two Chinese characters who are siblings too.
Graham Acker is a character that was meant to be a sort of parody of a typical American action hero, but American fans wound up loving him. So cast a typical Hollywood action hero lead as him (same choices you'd consider for Steve Rogers) and feature him prominently in at least one trailer and you should be set. And one of his comrades was African American.
The show has lots of Europeans, and Russians like Soma Peirez. Ali Al Sachez is either Spanish or Latin American. Aeolia Shenberg I think we can assume is an Ashkenazi Jew. And Louise Halevy is a Shephardic Jew, whom Hollywood often forgets exist.
Most of the Crew of the Ptolemaios is hard to tell since they go by code names and animation can be tricky to decipher ethnic features from, Alleluia I would also cast a Latin American actor for, to avoid any implications Sachez being the only Latin would have. The Lockon brothers are Irish. Sumeragi I think is also Japanese, or mixed.
I've still only scratched the surface. The story and cast is so massive I think you'd need at least 2 movies just to get the gist of season 1.