How to register a generic consumer adapter in MassTransit if I have a list of message types

Take a look at custom consumer convention here: https://github.com/MassTransit/MassTransit/tree/develop/src/MassTransit.Tests/Conventional

Create your own IMyConsumerInterface, IMyMessageInterface plug it in the code from that test. Register it ConsumerConvention.Register<CustomConsumerConvention>(); before creating the bus. It should work.

Additionally you can create your own wrapper around the consumer context and have that passed together with the message.

LoadFrom (MassTransit.AutofacIntegration) didn't work for me with the custom convention so I had to manually register consumers

foreach (var consumer in consumerTypes)
  cfg.Consumer(consumer, (Type x) => _container.Resolve(x));

---

Alternatively if you want to use "proxy" approach do something like:

public class WrapperConsumer<TConsumer, TMessage> : IConsumer<TMessage>
    where TMessage : class, IMyMessageInterface 
    where TConsumer : IMyConsumerInterface<TMessage>
{
    private readonly TConsumer _consumer;

    public WrapperConsumer(TConsumer consumer)
    {
        _consumer = consumer;
    }

    public Task Consume(ConsumeContext<TMessage> context)
    {
        return _consumer.Consume(context.Message);
    }
}

...

// create wrapper registrations
cfg.Consumer(() => new WrapperConsumer<MyConsumer, MyMessage>(new MyConsumer()));

---

additional code applicable to both approaches

// marker interface
public interface IMyConsumerInterface
{
}

public interface IMyConsumerInterface<T> : IMyConsumerInterface
    where T : IMyMessageInterface 
{
    Task Consume(T message);
}

...

builder.RegisterAssemblyTypes(ThisAssembly)
           .AssignableTo<IMyConsumerInterface>()
           .AsSelf()
           .As<IMyConsumerInterface>();

...

var interfaceType = typeof(IMyConsumerInterface);
var consumerTypes = AppDomain.CurrentDomain.GetAssemblies().SelectMany(x => x.GetTypes())
    .Where(x => interfaceType.IsAssignableFrom(x) && !x.IsInterface && !x.IsAbstract)
    .ToList();

---

RE: UPDATE 5

builder.Register(context =>
{
    var ctx = context.Resolve<IComponentContext>();
    var busControl = Bus.Factory.CreateUsingRabbitMq(cfg =>
    {
        cfg.ReceiveEndpoint(host, messageBusOptions.QueueName, consumer =>
        {
            foreach (var adapterType in adapterTypes)
                consumer.Consumer(adapterType, (Type type) => ctx .Resolve(adapterType));
        });
    });
    return busControl;
})