Eh, not really. Japanese names are quite common everywhere in One Piece.
Heck, the Germa siblings for example, who are named after Japanese numerals, plus their mother Sora. Yet, the patriarch is "Judge".
Or King Riku and his daughters Scarlet and Viola. Or Shirahoshi, daughter of Neptune.
True — sometimes Oda chooses Japanese names for the sake of a pun (e.g. the Vinsmoke siblings and Neptune’s children). I should mention that “Sora” and “Riku” are not necessarily Japanese names.
Other times, a Japanese name points towards the character being from Wano (e.g. Sentoumaru).
Part of my reasoning has to do with Uta’s hairstyle as well — which seems traditionally Chinese/Japanese. Let’s wait and see.
