This Visual Studio Code extension supports XSharp.Net (X#) with some syntax highlighting and code snippets. It is a (nearly) direct fork of 'xsharp-lang' in the 'vscode-xsharp-syntax' repository by Infominds Ag.
However, that instance did not provide any snippets, so I decide to make one.
This extension is based on that extension's current syntax (v1.0.3) which is for the current XLang (2.16).
Copy the 'pkg' folder as publishername.extensionname-versionnumber to %USERPROFILE%\.vscode\extensions (on Windows) or ~/.vscode/extensions (on Linux/ Mac) and restart VS Code,
or
download the .vsix file and choose 'Install from VSIX...' from the app.