Is this somehow related to Dynatrace monitoring your services or what is the use case here? Is the service broken after instrumented by Dynatrace? Or is this just a generic question not related to Dynatrace?
With Dynatrace you don't have any options to modify the calls between services or application or application behaviour. For any changes, you need to modify your application code or configuration.
Oh! My apologies. I overlooked the tag.
You are creating an HTTP monitor? AFAIK WS-Security is just an extension and you will need to add appropriate tags in your HTTP request payload.