"You are humans."
Translation:Vous êtes des humains.
"humain" can be a noun or an adjective.
singular noun: un humain (a human = one), plural: des humains (humans = more than one)
if you say "you are human" or "vous êtes humain(s)", it describes a personality trait (empathy, generosity...), not a factual state, where "you are a human being" would mean "you are not an animal".
I believe the English language moved this meaning of the humain adjective into humane. human can still be used as an adjective, but it is not inherently positive, it just means "of human species", therefore "You are human" can actually mean "You are a human" in English.
- You are humane => Tu es humain / Vous êtes humain
- You are [a ]human => Tu es un humain / Vous êtes un humain
- You are humane => Vous êtes humains
- You are humans => Vous êtes des humains
This is not a generality in French terms, it is just the plural of "you are a/one human".
Remember that "un/une" do have a plural form = des (indefinite article)
Generalities are constructed with definite articles; for example:
- les humains portent des vêtements = humans wear clothes.