meta-data

local-hostname: cloudimg

user-info

#cloud-config
# vim:syntax=yaml
users:
# A user by the name ec2-user is created in the image by default.
  - default
# Following entry create user1 and assigns password specified in plain text.
# Please not use of plain text password is not recommended from security best
# practises standpoint
  - name: user1
    groups: sudo
    sudo: ['ALL=(ALL) NOPASSWD:ALL']
    plain_text_passwd: password
    lock_passwd: false
# Following entry creates user2 and attaches a hashed passwd to the user. Hashed
# passwords can be generated with:
# python -c 'import crypt,getpass; print crypt.crypt(getpass.getpass())'
#  - name: user2
#    passwd: < hashed password here >
#    lock_passwd: false
# Following entry creates user3, disables password based login and enables an SSH public key
#  - name: user3
#    ssh-authorized-keys:
#            - < ssh public key here >
#    lock_passwd: true

chpasswd:
  list: |
    ec2-user:password

is the file name "user-info" correct? I ask because the official page uses user-data instead:
https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/amazon-linux-2-virtual-machine.html#amazon-linux-2-virtual-machine-prepare

But I had trouble getting seed.iso based on the info from that page to work, and init.iso worked like a charm.