I'm looking for functionality similar to the "Create Unit Tests" feature of Visual Studio, for the .NET Framework (full/classic). I'm aware of "dotnet new mstest" or similar, but for an existing project, this does not work well, and will only generate one test file to start with.
I know of the dotnet cli global tools feature, but did some searching and didn't find what I was looking for.
Try Unit Test Boilerplate Generator from the Visual Studio Marketplace.
Also, please submit feedback (via Visual Studio) asking for Create Unit Tests to be supported on .NET Core projects.