Wiktionary claims that "människa" does mean "manish" (and that it's a direct cognate with "mensch"):
https://en.wiktionary.org/wiki/Reconstruction:Proto-Germanic...
It's just that that etymology has become opaque to modern-day Germanic language speakers.
But "människa" is a noun. It's pronounced "menisha" but it doesn't mean "manish". In Norwegian, the word for humane is spelled "menneskelig" literally "menneske-like". (In Norwegian the 'k' is hard.)
As I can gather, the literal meaning in sanskrit of "manusha" = "born of Manu" = human. Manu is a god.