All kinds of race-washing is bad.
You might have seen a lot of discourse about race-swapping/washing in the art community (or maybe I'm just on a weird part of tiktok). A lot of it is about whether if it's alright to change a character, who is either canonically or just visually shown to be, for example, asian, to be black instead. I've mostly seen this being discussed about an artist (can't remember their name or anything rn), who made an animation where the girls from Doki Doki Litterature Club were drawn as poc (significantly darker skin, dreads/braids/afros, etc.). A lot of the people, who said this wasn't an issue said, that it was because the girls don't have canon ethnicity - whether that is correct or not I'm unsure, since I haven't been able to find any official statement about it. But still, I personally find an issue with this, albeit in a different way than I've seen others discuss it.
To quickly comment on the whole "the Dokis don't have a canon ethnicity"-thing, I think it's a bit of a weak excuse - the Dokis are visually shown to be pale - whether they are white, asian, or anything else is up for debate. Although, I think the fact that the characters have japanese (specifically Sayori and Natsuki, but also Yuri), the words "doki doki" is a way to describe the quick beating of a heart (the same way we say "knock knock" in english), and more indirect hints, like the style of their uniforms, the layout of the school (specifically the desks), etc. This all points to a japanese setting, and the fact that even if the characters might not be explicitly stated to be racially japanese, I personally think they are. If every character had to have a scene, where they stated their specific ethnicity, it would be a really crappy game. So, again, I personally believe, that the Dokis are japanese, or at least some kind of eastern asian.
Now, onto the debate about "blackwashing": The term "blackwashing" is a word the art community has made for characters, who have had their race (whether canon or not) changed to be black. usually, this includes african hairstyles, and sometimes, albeit less often, facial construction. "Blackwasing" comes from "whitewashing", which is widely accepted to be extremely racist - poc get their race/ethnicity changed to being white/more pale. Whitewashing is rooted in the idea, that the more pale a person is, the more beautiful/pure/clean they are, which is an extremely racist belief, and absoloutely not okay. A lot of people say blackwashing isn't real, since blackwashing isn't built on the same belief (that the darker a character's skin is, the more beautiful/pure/clean they are). Although, in my opinion, even if blackwashing isn't based on that ideology, it's still bad, which I'll explain why in a bit.
But first, I'd like to say, that from my experience, I would say the darker a character's skin is, the more likely they are to be whitewashed, yet when it comes to blackwashing, I'd say it's more often asians, who become blackwashed, and not so often hispanics, eastern europeans, south americans, and many other kinds of poc. An example of this is Doki Doki Litterature Club, where four characters (who are heavily hinted at being japanese yet are never directly said to be so) are extremely often depicted by fans to have darker skin - but they aren't the only ones. Characters like Raiden Ei from Genshin Impact, bazically all characters from Demon Slayer, but especially Rengoku, and probably may others that I have missed.
I find a bit of an issue with this, because in times and situations like japan in the early 1900's, being a person of color would massively change your experience in life. Take for example Rengoku, a person from a long lineage of respected demon slayers. He is well liked among his community, and he is looked up to by many. Rengoku has a lot of social and economic status, which he, historically, never would've had, if he was a person of color. Let's say Rengoku was african - then he never would've come anywhere near a high social status in 1915 Japan. The japanese had many of the same racist perceptions of poc as white people had, and he would be massively looked down upon for it. Even if he was somehow born into the same family lineage and rank as the original, his character, from his experience growing up as a poc in a very racist country, to the automatic distrust, disgust and fear many would hold against him, would 100% change. In this case, making Rengoku black would change his experiences and character so much, he would hardly be the same person anymore.
My main point here is, that changing an asian (especially a japanese) character's race to be black erases the experiences of real life black people growing up in very racist countries - and I can speak from my own experience. Now, I'm not a person of color (or anything close to that, haha), but I do live in an extremely racist part of Denmark, where the few poc that live here often get driven to moving away or even committing suicide to escape the racism that exists here. I've seen countless of friends, family, strangers and others get treated in such a different way from me, all because of the melanin in their skin, and I think it's bullshit. And what's happening - both in the past and today - in Japan is the same situation, but 1000000 times worse. Because sadly, poc get such vastly different experiences in life for looking different.
Again, this is just my opinion. It's not my job as a pasty white person to say what's right or wrong about race-swapping or anything like that. That's up to the people it affect, not the people who decide who it affects.
If you made it all the way through this rant, thank you! I'm sorry if anything I have said has come off as discriminatory, racist or anything else. That has never, ever been my intention. Again, this is my opinion on the matter, not some inherent truth or a debunking of other people's opinions.