A. Create a snapshot of the source DB instance in the source account. Share the snapshot with the destination account. In the target account, create a DB instance from the snapshot. Most Voted
B. Use AWS Resource Access Manager to share the source DB instance with the destination account. Create a DB instance in the destination account using the shared resource.
C. Create a read replica of the DB instance. Give the destination account access to the read replica. In the destination account, create a snapshot of the shared read replica and provision a new RDS for MySQL DB instance.
D. Use mysqldump to back up the source database. Create an RDS for MySQL DB instance in the destination account. Use the mysql command to restore the backup in the destination database.