Pixiv user name is 形昇Nishikino, but he usually signs his work as Nishikino形昇 (see Danbooru post #4182446).
From his commentary it appears Chinese is his native/preferred language, but Danbooru post #4182873 suggests that 形昇 should be read as "Kadaji (Katachi) Noboru", which is a Japanese reading. The Mandarin Chinese reading of the same characters would be "Xíng Shēng".
https://www.pixiv.net/users/46440369
https://www.pixiv.net/stacc/user_wcxr8257
https://twitter.com/Nishikino15419
https://twitter.com/intent/user?user_id=1469548994363736065
https://space.bilibili.com/28470085
https://www.miyoushe.com/sr/accountCenter/postList?id=270958473
https://ximuyexingsheng.lofter.com