Would a greatbow (bow from the souls games) work? It's about the size of a person and shoots huge arrows, they were made to kill dragons but I'm wondering if you could actually use a person sized bow in real life.
It really depends on what you think qualifies! English/Welsh Longbows and Japanese Yumi bows are both very long, and can easily get well over 6' end to end. Yumi in particular have a very long draw (as do e.g. manchu bows), and use very long arrows (3ft+).
The draw weight on some of these bows also goes very high (warbows are generally 80-180lb, but can hit 200lb in extreme cases), so drawing them is also like lifting a person.
The thing that video games, etc. Often get "wrong" (though tbh it's generally a deliberate stylisation choice) is that just making a bow bigger doesn't make it inherently more powerful- a well-made asiatic war bow could hit similar weights to a longbow, while being a good foot or so shorter, and due to their different speeds, may shoot arrows that have greater range and more energy on impact. (But the longbow is designed for heavier arrows so it gets complicated when looking at armour tests, etc.)
Similarly, if you just keep making the limbs thicker, you'll get diminishing returns, and eventually the material will hit its limits and it won't function like a bow any more. Or it will, but nobody can physically use it.
So essentially yes, but there are limits.
