Update: .NET Core 2.0 allows to use Visual Basic to develop .Net Core apps.
Support for Visual Basic
In addition to supporting C# and F#, 15.3 now also supports using Visual Basic to develop .NET Core apps. Our aim with Visual Basic this release was to enable .NET Standard 2.0 class libraries. This means Visual Basic only offers templates for class libraries and console apps at this time, while C# and F# also include templates for ASP.NET Core 2.0 apps. Keep an eye on this blog for updates.
Support for Visual Basic
In addition to supporting C# and F#, 15.3 now also supports using Visual Basic to develop .NET Core apps. Our aim with Visual Basic this release was to enable .NET Standard 2.0 class libraries. This means Visual Basic only offers templates for class libraries and console apps at this time, while C# and F# also include templates for ASP.NET Core 2.0 apps. Keep an eye on this blog for updates.
For starting here is a tutorial for building a Visual Basic Hello World application with .NET Core.
ASP.NET Core 1.1 still doesn't have support for VB compiler. You may monitor progress by this issue in dotnet/cli repo.