Migrate existing SSO config to delegated AWS Account

We've read with interest the new SSO delegated member account functionality - https://aws.amazon.com/about-aws/whats-new/2022/05/aws-sign-on-administer-delegated-member-account-in-organization/

Does anyone happen to know if there's an easy way to migrate existing configuration from the current management account into the delegated account without doing it manually, user by user, group by group, account by account?

We have quite a few users and permission sets 😊

Many thanks in advance.