MS released a Nuget package which registers the EventSource class after build:
Registering your EventSource
When you install the EventSource NuGet package, the build step previously mentioned generates the following files for each EventSource in your application:
<AssemblyName>.<EventSourceTypeName>.etwManifest.man <AssemblyName>.<EventSourceTypeName>.etwManifest.dll.
These files need to be registered with the operating system to enable channel support. To do this you run the following command after the files are in their final deployed location:
wevtutil.exe im <EtwManifestManFile> /rf:"<EtwManifestDllFile>" /mf:"<EtwManifestDllFile>"
Once this registration command is executed, all subsequent calls to MinimalEventSource.Log.Load(), from any process on that machine, will automatically result in events in the Windows Event log.
After registering it you should see it in all tools which read the installed providers.