Change the passwords for multiple users by using
stdin
. More information: https://manned.org/chpasswd.8.
printf "username:new_password" | sudo chpasswd
printf "username_1:new_password_1\nusername_2:new_password_2" | sudo chpasswd
printf "username:new_encrypted_password" | sudo chpasswd --encrypted
printf "username:new_password" | sudo chpasswd --crypt-method NONE|DES|MD5|SHA256|SHA512