Kanji for achikinashi

It writes あちきなし (achikinashi), a classical Japanese adjective for futility or helplessness. It describes something pointless, unsatisfying, or beyond one’s power to change.

Its older form, あづきなし (azukinashi), appears in the 8th-century 万葉集 (Manyōshū); the later あぢきなし (ajikinashi) also described futile, unchangeable situations.

Is 𪬿 Japanese-made?

Yes: 𪬿 is a Japanese-made kanji for a native Japanese word.

It appears in 大塔物語 (Daitō Monogatari), a medieval war tale about a 1400 battle in Shinano (now Nagano). An 1851 print reproduces a manuscript with a 1466 copying note; those dates do not mark the glyph’s creation.