If the cloned-object(from EnsLib.HL7.Message) instead of original is used in the ClassMethod that Christina defined above the "assign" action would work. But the question is how to make the "send" action to send the cloned-object?

I see the following, run it and get "Error: mensagem immutable"

How to use the cloned-object(from EnsLib.HL7.Message), have multiple rules (in the same RuleSet) share it one after another, and finally send it instead of original EnsLib.HL7.Message. 

A list of business rules (defined in a process) to run before sending to target(an operation)

The following case does not work due to mensagem immutable (As EnsLib.HL7.Message):

https://community.intersystems.com/post/how-assign-value-variable-business-rules-using-function

"The purpose is to edit the HL7 ORU R01 message"