When you migrate to MySQL Database Service on Oracle Cloud Infrastructure (MDS on OCI), the easiest, fastest and recommended way it to use MySQL Dump & Load Utility.
For more information check these different links:
MySQL Shell performs all the checks required also for copying users to MDS when using
This is the safest way to migrate data to MDS as when the
ocimds option is enabled, you have the possibility to skip accounts which use authentication methods (plugins) not supported by the MySQL Database Service but also to remove certain privileges that are restricted in the MySQL Database Service.
But sometimes you may only want to copy a user (or some) to one server to another one. And that destination server can also be a MDS instance.
If you are interested, this is how it works: