I don't know if I understood correctly your question, but I see clearly a couple of misunderstood concepts, let me guide you on how I think you should face this:
- The SlingModel exporter requires a selector and a resourceType in order to be invoked, the result of this invocation is a JSON output, which I assume is what you will pass to your react team. Please check this to understand how you can achieve this: https://experienceleague.adobe.com/docs/experience-manager-learn/foundation/development/develop-slin...
- The SlingModel exporter relies on the Jackson framework, which in short, will produce a JSON output based on the "getters" method found in your SlingModel, that means, if you add, for example, a method called getPageName(), the final JSON output will append a property called "pageName" and the value will be the return statement from the getPageName() method.
- The core components had implemented the "ComponentExporter" for the resourceType "page", this is a default implementation that you can take advantage of, you can learn more here about it: https://experienceleague.adobe.com/docs/experience-manager-65/developing/components/json-exporter-co.... But this is a default "basic" implementation, you can inherit and built on top of it or you can create your own implementation which suits your needs.
Hopefully this clarify your doubts.
Esteban Bustamante