The requirement is to add “required” validation on input-output parameters of bpmn:callActivity and make it visible on the properties panel UI.
<bpmn:callActivity id="Activity_00lde5i" name="BPO Common - Create Resource 2" calledElement="bpocommon_ForceTerminateResource">
<bpmn:extensionElements>
<camunda:inputOutput>
<camunda:inputParameter name="input_map_1">
<camunda:map>
<camunda:entry />
</camunda:map>
</camunda:inputParameter>
<camunda:inputParameter name="resource_input_1" />
<camunda:outputParameter name="resource_output" />
</camunda:inputOutput>
</bpmn:extensionElements>
</bpmn:callActivity>
Something like as shown in case of calledElement