Sure it is...
(This is my suggestion for
everything 
...
Put an Ability Source at
every gravitywell, using the GalaxyScenarioDef file, with the ability you want. Have your scouts auto-capture the Ability Source when they first explore the system (this is the trickiest detail), and viola!!!
The Ability Source is a short way of saying "Invisible/Indestructible/Immobile frigate whose only purpose is to deliver the ability to every target in the galaxy simultaneously"
The same thing was done with the network of stargates to defeat the replicator version of me, so it should be a piece of cake...