I have created two different Developer Portals to separate my APIs. Is it possible to view ALL of my published products (from both Portals) in a single Portal? For example, I want to have a public Developer Portal that only shows a subset of my products but an internal Portal that shows all of them. How can I do this?
A single portal site always represents a single catalog in APIC. If you want to see an aggregated view of the data from multiple catalogs then you need to use the syndication capabilities in APIC to publish the content to a single catalog. That parent catalog can then have a portal site that has all of the content in it.
If you want two portals, you need two catalogs.