https://twitter.com/visegrad24/status/1496788626658807814
edit: Wait no, it's maybe worse. That's the Ukrainian ambassador to Japan so this is actual weeaboo cosplay: https://www.theweek.in/news/world/2022/02/16/ukrainian-ambassador-to-japan-poses-as-samurai-in-message-to-russia.html
Along with the impressive image, Korsunsky wrote in English and Japanese "We know what we are fighting for. How about Russia?"
Sergiy Korsunsky
I searched around for some mention of his ancestry but didn't see any. Prior to this he also served as US ambassador and has a degree in international relations, so it might be an arbitrary assignment in the way that the State Department rotates diplomats through different countries before giving them an ambassadorship they want.
edit: And the great grandfather mention on the original image is seemingly a false story from this twitter user mistaking them for the Japanese ambassador to Ukraine rather than the other way around.
Alright in that case yeah maybe he's a weeb.