Azure Active Directory is not designed to be the cloud version of Active Directory. It is not a domain controller or a directory in the cloud that will provide the exact same capabilities with AD. It actually provides many more capabilities in a different way.
That’s why there is no actual “migration” path from Active Directory to Azure Active Directory. You can synchronize your on-premises directories (Active Directory or other) to Azure Active Directory but not migrate your computer accounts, group policies, OU etc.
There are new Frankfurt and Berlin datacentre regions coming up, so Azure AD DS should be available in Germany soon.