(Fear not) the power of man, for none of woman born shall harm Macbeth.
So, the keywords in the prophecy are "man," "woman," "born," and "harm." Miss any one of these and you can kill macbeth. Let's go through them in order.
Man
Obviously, anyone who isn't a man can kill macbeth; this includes women which is territory that's been explored pretty throughly, but also nonbinary people who also aren't men (nonbinary men are a demographic that exists). Genderfluid characters might flux between being able to kill him and not kill him depending on whether or not they are currently a man.
Further out from this, animals which aren't human (or are otherwise excluded from the category of manhood) can kill macbeth. That was obviously scratched by the constrants of the prompt, but I'll put a pin in that.
Lastly, there's a group we've yet to consider; see the man-woman binary described by western hegemony isn't actually best described as a binary, but a quaternary between the binary genders and the binary maturities: this is man and woman yes, but there is also child and adult; which together make man, woman, boy, and girl. I'd argue that anyone juvinille enough to be considered a boy but not a man could kill macbeth.
From these categories, we find the following characters can kill macbeth:
Woman
I mean, there's only one way around this and it's that the person who birthed you wasn't a woman at the time you were born. If your birthing parent was: a trans man, a gender fluid person who during the birth wasn't a woman, a man, as (previously established non-human or otherwise excluded from womanhood), or (as previously established) a boy or girl, congratulations on your ability to kill macbeth.
I'd also happily argue for the sake of prophecy that if the birthing mother died during labor before you were out then you weren't born from a woman but a corpse.
- Poof Poof (Fairy Odd Parents)
- The Chestburster (Alien)
- Seahorses (real life)
- Hakari Hanazono (100 Girlfriends, born to a 13 yo mother)
- Jesus Christ (Mary in most common interpretations is teen-aged)
- Elphaba (Wicked)
- Deadshot Calamity (Fallout:Equestria)
- Gaara (Naruto)
Born
The classic interpretation of the prophecy uses this particular loophole, that if you ain't come out of the birthing canal kicking and screaming, you weren't "born." Then, C-sections babies can kill Macbeth.
So too can anything which hatched, spawned, or was created or built.
You could also argue that several forms of Isekai reincarnation don't function as births but as possession.
- Daffy Duck
- Perry the Platypus
- Orcs (LotR)
- Dani Fenton
- Aziraphale and/or Crowley (Good Omens) or most christian angels and demons from most media actually.
- Data (Star Trek), C3P0/R2D2 (starwars), or any android actually.
- Pinnochio
- Frankenstein's Monster
Harm
This one is interesting because there's a little hiccup here that I don't think you're expecting. Harm according to some definitions requires intentionality. A sword doesn't harm you: the person weilding it does.
There are some characters that you wouldn't expect would be able to hurt Macbeth; but, if we consider intentionality a necessary part of harm, there are some characters who are excluded but can be used by others to kill Macbeth, and it's an approach you don't see considered.
Linguini piloted by Remy (Ratatouille)