Referencing .NET Standard 2.0 packages is supported using the following:
- NuGet 3.6.0 or higher for VS 2015 (from NuGet’s download site – may not yet be listed as recommended latest)
- Install the “.NET Standard Support for Visual Studio 2015” from https://aka.ms/netstandard-build-support-netfx (NuGet in VS will also print a link to this in its output window).
There are a still few bugs when consuming .NET Standard 2.0 libraries, especially when mixing .NET Standard < 2.0 and 2.0 libraries but these updates give basic support.