System Center 2019 Datacenter: $3,607 or Standard $1,323 per managed endpoint (up to 16 physical cores). Windows Admin Center - NEW (Free), Microsoft Azure
The System Center 2016 Datacenter license model is like Windows Server 2019. A single licence covers 16 physical cores on a server. If the server has more CPU, you need to buy extra licences packs. The System Center 2019 standard is based on managed endpoint.
For virtualize environment, you just have to buy licenses for the Hyper-V hosts.
Windows Admin Center is a new web-based management tool for Windows Server. It can genuinely replace some MMC console such as firewall, explorer, device manager and so on. Windows Admin Center is built on extensions that add some new capability to the product. Third party vendors can develop extensions for Windows Admin Center.