Add Model Project (EntityFramwork) to Asp.net Core 3 Project

I have 3 projects in my Solution like below:

1. ModelProject (EntityFramework)
2. ProjectA (ASP.NET MVC)
3. ProjectB (ASP.NET CORE 3 with Blazor)

So in model project i defined my tables ,relations, queries and their classes then added that on ProjectA and ProjectB.

on ProjectB (.net core) in startup.cs by services.AddDbContext tries to add dbcontext (ModelProject) but get this error:

Cannot convert lambda expression to type 'ServiceLifetime' because it is not a delegate type

Is this error for using EF on Core Project? how can i solve it?

ProjectB (Core):

services .AddEntityFrameworkSqlServer() .AddDbContext<Models.DataContext>(options => { options.UseSqlServer(Configuration.GetConnectionString("DataContext")); });

and dbcontext (EntityFramework Standard):

namespace ModelProject
{
    public class DataContext : DbContext
    {
        public DataContext() : base("DataContext")
        {          
            Database.SetInitializer(new MigrateDatabaseToLatestVersion<DataContext, Migrations.Configuration>());
            (this as IObjectContextAdapter).ObjectContext.ContextOptions.UseCSharpNullComparisonBehavior = true;
            ((IObjectContextAdapter)this).ObjectContext.CommandTimeout = 300;
         }
     }
}