This server role is also available in Windows Server Essentials and is enabled by default. Before you install Windows Server Essentials or the Essentials Experience role, note the following limitations. – Must be the domain controller at the root of the forest and domain, and must hold all the FSMO roles.
Does Windows Server 2019 Essentials have to be a domain controller?
If configured as a Domain Controller, Windows Server 2019 Essentials must be the only Domain Controller, must run all Flexible Single Master Operations (FSMO) roles, and cannot have two-way trusts with other Active Directory domains.
Can Windows Server 2016 Essentials be a domain controller?
Note: Windows Server Essentials can only be deployed as domain controller. In this document, Windows Server Essentials does not include Windows Server Essentials.