Method not found: 'Void EntityFrameworkCore.Design.Internal.DbContextOperations

https://docs.microsoft.com/en-us/ef/core/get-started/aspnetcore/existing-db?view=aspnetcore-2.0#install-entity-framework

I suspect you are missing the assemblies that are necessary for scaffolding? I also assume you are trying to reverse engineer an existing db?

example Scaffold-DbContext "Server=(localdb)\mssqllocaldb;Database=Blogging;Trusted_Connection=True;" Microsoft.EntityFrameworkCore.SqlServer -OutputDir Models

if it fails like i can't find it might be a pmc issue, try closing down VS try again. After that its probably a configuration with missing assemblies.