Generics.cs

using System;

public sealed class Dummy<T> { private Dummy() {} }

public interface IInterfaceA { }
public interface IInterfaceB { }

public class Hoge : IInterfaceA { }

public class Sandbox
{
    public static void Call<T>(T item, Dummy<IInterfaceA> dummy = default) where T : IInterfaceA => Console.WriteLine($"{item} is A");
    public static void Call<T>(T item, Dummy<IInterfaceB> dummy = default) where T : IInterfaceB => Console.WriteLine($"{item} is B");
}

Sandbox.Call(new Hoge()); // Hoge is A