How can you market a book if you don't speak the language in that country?
This overlaps a bit with your previous post, but might be the most challenging part of this approach. Unless your Japanese is advanced, you might have to pay people to help you translate marketing materials. Luckily, Japanese social media is particularly private and it wouldn't be unusual to not have any personal photographs.
Using a pseudonym from a different race automatically create expectations for the reader.
A very relevant example is 石黒, 一雄 (Kazuo Ishiguro). Ishiguro is Japanese, but moved to England when he was 6. I like to approach books without any context and didn't read anything about him or the book before reading Remains of the Day. However, I was trying to broaden the amount of Japanese authors I had read. While I certainly don't regret reading the book, especially since Ishiguro is such a famous author, I don't consider Ishiguro "Japanese" and presume he has more in common with an English person. I would have preferred to have read a book by an author that lived in Japan until they were at least 18.
Note that other ethnicities living in Japan will also use Kanji names - Wikipedia.
More and more fans of Japanese culture are adopting Japanese names.
It looks like this is now a norm. I looked up "spam calls" on Twitter to check for reports on malicious calls and one of the first few entries was あかり (@manekikarasu), not sure if it appropriate to share Twitter links though). Do note that this Twitter user is using kana, which makes it unclear whether they are Japanese or not.
Other options - Transparent Bio
There's an important difference between using a pseudonym and pretending to be a different ethnicity. If you use a Japanese name, but openly state authentic information in your bio, no one will likely have a problem. This is analogous to when I use female avatars in games. Why would I use a male character and stare at a male all day? Instead you simply put "male" under gender and people might not be bothered by it in a MMORPG.
Similarly, you could state that you are using a pen name, but then go on to describe a fictional author.
However, those option wouldn't be very interesting, would they?