ASP.NET Core - custom AspNetCore.Identity implementation not working

I'm building a completely custom AspNetCore.Identity Implementation because I want TKey to be System.Guid across the board. With respect, I have derived types for...

• Role : IdentityRole<Guid, UserRole, RoleClaim>
• RoleClaim : IdentityRoleClaim<Guid>
• User : IdentityUser<Guid, UserClaim, UserRole, UserLogin>
• UserClaim : IdentityUserClaim<Guid>
• UserLogin : IdentityUserLogin<Guid>
• UserRole : IdentityUserRole<Guid>
• UserToken : IdentityUserToken<Guid>
  
  
• ApplicationDbContext : IdentityDbContext<User, Role, Guid, UserClaim, UserRole, UserLogin, RoleClaim, UserToken>
  
  
• ApplicationRoleManager : RoleManager<Role>
• ApplicationRoleStore : RoleStore<Role, ApplicationDbContext, Guid, UserRole, RoleClaim>
• ApplicationSignInManager : SignInManager<User>
• ApplicationUserManager : UserManager<User>
• **ApplicationUserStore** : UserStore<User, Role, ApplicationDbContext, Guid, UserClaim, UserRole, UserLogin, UserToken>

ApplicationUserStore is the problem child!

Implementation

namespace NewCo.Identity
{
    using Microsoft.AspNetCore.Identity.EntityFrameworkCore;
    using System;

    public sealed class Role : IdentityRole<Guid, UserRole, RoleClaim>
    {
    }
}

namespace NewCo.Identity
{
    using Microsoft.AspNetCore.Identity.EntityFrameworkCore;
    using System;

    public sealed class UserRole : IdentityUserRole<Guid>
    {
    }
}

namespace NewCo.Identity
{
    using Microsoft.AspNetCore.Identity.EntityFrameworkCore;
    using System;

    public sealed class RoleClaim : IdentityRoleClaim<Guid>
    {
    }
}

// The problem is here...

namespace NewCo.Identity
{
    using Microsoft.AspNetCore.Identity;
    using Microsoft.AspNetCore.Identity.EntityFrameworkCore;
    using System;
    using System.Security.Claims;

    public sealed class ApplicationUserStore : UserStore<User, Role, ApplicationDbContext, Guid, UserClaim, UserRole, UserLogin, UserToken>
    {
    }
}

Error

The type 'NewCo.Identity.Role' cannot be used as type parameter 'TRole' in the generic type or method 'UserStore'. There is no implicit reference conversion from 'NewCo.Identity.Role' to 'Microsoft.AspNetCore.Identity.EntityFrameworkCore.IdentityRole>'.

As far as I can see, unless this is some (co/contra/in)variance issue, all the code checks out...what did I get wrong?