New version(s) of the XSharp Plugin for IL-Spy are available : One for IL-Spy 4, and the other one for IL-Spy 5.
If you don't know, ILSpy is the open-source .NET assembly browser and decompiler, and you can use ILSpy to view and decompile .NET assembly as XSharp Language.
To do so, first get the ILSpy binaries and unzip them in a folder.
Then get the ILSpy Plugin in the Downloads/General/Tools section, and unzip the DLL in the same folder as the ILSpy Binaries.
Now, when running ISpy, you can set the language as XSharp.
The full source code of the Plugin is available in the public XSharp Repository on Github; you can also view there the current state of developement of the tool ( What is working currently, Changelog, ... )