I ionised Guri the other day , and was like you don't have Focus on your action bar so no action for you. However my opponent argued that the wording " During the Perform Action step, the ship can perform only the [Focus} action. " actually allowed his ship to do an action it wouldn't normally have. I know there is a few examples of upgrades allowing ships actions that aren't on their action bars, Afterburners for example, so couldn't point to a definitive rule to dissuade him.
Though an Ionised droid pilot thematically should be more distracted than a organic pilot!
So what should it be, no action, focus, or calculate?