You'll need a DLL to use SharpPN. So once you have that, just build and specify the dll path in the command-line arguments.
You can build yourself with C:\Windows\Microsoft.NET\Framework64\v3.5\csc.exe -out:SharpPN.exe C:\Path\to\Program.cs
or by opening the .sln file with Visual Studio and building there.
.\SharpPN.exe -DLL C:\path\to\your\dll
Caleb Stewart & John Hammond's PowerShell PoC: https://github.com/calebstewart/CVE-2021-1675