Share request/responses between modules/services

Question

I'm writing monolith application that consists from multiple modules. For the sake of example there are two modules: Module_B depends on Module_A.

To achieve low coupling and make it easier to split my monolith to separate services in future, I arranged communication between Module_B and Module_A through ModuleAClient (see code below).

Should I share some of Module_A's request/response objects or duplicate them inside Module_B?

Share Module_A request/response

In example below I pass com.moduleA.ModuleARequestObject to and return com.moduleA.ComplexGraphResponse from buildGraph method. That mean that com.moduleA.* objects are spread across Module_B's classes. Does it mean higher coupling? If I change ComplexGraphResponse inside Module_A, Module_B will also change it behavior (may be broken).

Duplicate Module_A request/response

In other hand, duplicating some of complex Module_A request/response objects is an extra work and I can't see how it save me from high coupling. If I change ComplexGraphResponse inside Module_A, Module_B will fail to map ComplexGraphResponse to ComplexGraphResponseBDuplicate and will also fail.

Example

package com.moduleB.client;

// QUESTION: should I map moduleA request/response objects to moduleB request/response objects?
import com.moduleA.ComplexGraphResponse;
import com.moduleA.ModuleARequestObject;

//This class is located inside Module_B
@Service
public class ModuleAClient {

    @Resource
    private ServiceA serviceA;

    public ComplexGraphResponse buildGraph(Set<ModuleARequestObject> objects) {
        return serviceA.buildGraph(objects);
    }     
}

P.S.

I have found this question. Is it the same? Do you agree with response?