There used to be a word for "you" in English that was used or more than one person: ye: "you are good" for one person and "ye are good" for more than one person.
This word has more or less disappared from English, although in some colloquial usage people sometimes say "yous" as a plural - "where are yous guys going?"
Te reo Māori has a plural form of you: koutou.
When greeting a crowd you might say:
Tēnā koutou!
Literally: There you all are"
Greetings to you.