How to execute one call with multiple base urls

The collection runner\data file method would be the recommend way.

The only other way is to use a script\loop with setNextRequest() which also needs the collection runner to work. Please search the forum for examples.

The following has an example that you can use as a starting point.

How can I add the loop? - :seedling: Just Getting Started - Postman Community

Instead of having an array of numbers, you would have an array of URL’s.