CQRS - sending response by command with immediate consistency

It's not hard, instead of sending a command, you can call directly the command handler from controller. Or have a service method which will handle the input and returns something. The important bit is that all these are done synchronously (i.e you need to wait until the handler finishes). The domain events handlers are unaffected, they can be async.

If you don't want to go 'hybrid' and want to always use the same workflow (as described in your pic) things are more complicated, you need the client to check often if the operation has completed. I think the better way is to be flexible so, for some tasks you can use the 'old' ways. The domain events will still be generated and handled, that part would not change. You're just changing the way a 'command' is executed.

Also, it's worth mentioning that you shouldn't expect responses from event handlers and if it makes you feel better, use the 'request-response' terminology instead of command-response.

Btw, you don't break CQRS this way, as long as your domain model isn't used to do queries i.e you have different model for writes and reads, it is CQRS.