Natsuki

Natsuki is also used as a masculine name in Japanese. However, it's more common for females. So, I think that the "Gender" of this name should be changed from "Feminine" to "Feminine & Masculine". For evidence of Natsuki also being used as a masculine name, see comments below this one.

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Sources: https://en.m.wikipedia.org/wiki/Unisex_name
https://forebears.io/x/forenames/natsuki
https://en.m.wikipedia.org/wiki/Natsuki

This is also a boys’ name in Japan, only spelled as 夏樹。.

If written as 夏樹, Natsuki can also be used for males.

Natsuki used as "なつき" is 202nd place in terms of sound among males. (source: http://5go.biz/sei/cgi/ninki1.htm).

Is also commonly used as a boy's name in Japan.