This script copies your keypair to any regions missing it based solely on the keypair name and not the fingerprint.

ec2-import-keypair-all-regions.sh

#!/bin/sh

set -o errexit
set -o nounset

usage() {
  echo "Usage: ${0} keypair_name public_key_file"
  exit 1
}

[ $# = 2 ] || usage

keypair=${1}
pubkey=${2}

regions=( $(ec2-describe-regions | awk '{print $2}') )

keypair_exists() {
  ec2-describe-keypairs ${keypair} --region ${1} >/dev/null 2>&1
}

import_keypair() {
  ec2-import-keypair ${keypair} --public-key-file ${pubkey} --region ${1} >/dev/null
}

for region in ${regions[@]}; do
  if keypair_exists ${region}
  then
    echo "The keypair '${keypair}' already exists in region '${region}'"
  else
    import_keypair ${region}
    echo "The keypair '${keypair}' was imported to region '${region}'"
  fi
done