Human nature refers to the essential quality/characteristics of something, what it is to be man/woman vs animate or inanimate creation or Deity. A female nature includes common human characteristics with males, but sexual organs and genetic matter (XY vs XX, penis vs vagina) differs.
The nature of fire is to burn. The nature of salt is to preserve. The nature of a rock is to sit there. The nature of God uniquely relates to Him being sovereign, uncreated, eternal, spirit, triune, omnipotent, omniscient, omnipresent (unlike us). The nature of being human is to be personal with will, intellect, emotions (God and angels have this, but no physical body), blood, guts, spirit, body, bones, etc. Humans are different than primates because we are in the image of God (does not mean physical image like Mormons teach).
Human nature is what it means to be human vs God, angel, rock, dog, fire, wind, TV, computer, car, sun, moon, etc.
It is not essential on a metaphysical/physical/ontological/being/substance level for humans to be sinful since sin is a moral/volitional issue, not a physical, genetic, metaphysical/being issue.
Don't follow Augustine, Plato, Aquinas in their philosophical errors that have been uncritically embraced by lazy Christians. Follow Scripture that agrees with the gist of my view (even secular philosophers understand these distinctions better than some Christians who trust Aquinas more than common sense and Scripture).
No, I am not worried about my views on this subject sending me to hell because they won't. Denying Christ's Deity/humanity/sinfulness is an issue that I am not guilty of (nor are you or AMR).