.NET Core 3 now supports System.Management. As of this time, .NET Core 3 is in preview mode with preview 4 as the most current.
You will have to select the Manage NuGet packages… menu item under the Project menu in Visual Studio to install the latest version of System.Management. Make sure that the include previews checkbox is selected so that you will install the latest version.
The previous version of System.Management throws an error:
“Cannot marshal a string by-value with the [Out] attribute…”
See this link for more info about the error.