Currently, you cannot enable Progressive Web App (PWA) functionality directly for a Reactive Web Application (RWA) in OutSystems Developer Cloud (ODC). PWAs are specifically supported as a distribution mode for mobile apps created with Phone App or Tablet App templates in OutSystems. To enable PWA functionality, you would need to create a mobile application, either from scratch or by reusing components from your existing Reactive Web App, and then enable the "Distribute as PWA" option for that mobile app.

From the articles, it appears that OutSystems allows PWA distribution to be toggled on directly within the app details of a mobile app. However, this is not extended to Reactive Web Apps Distribute as a progressive web app.

As a workaround, you could potentially reuse some of the logic or components from your existing RWA if they are implemented using reusable custom web blocks or server actions. This would allow for some architecture overlap between the two applications.