Not sure even instants can do that. I have some old code. Maybe newer code can. This is a controller function like ap-groups.
I remember the term "AP groups" from Cisco WLC configuration and certainly Aruba offers identical or similiar functionality. It allowed you to do that, but for me configuration was somewhat counter-intuitive for me. I suppose at some level it is acceptable not to have all the features available to reduce complexity and also to draw a line in between product lines. Aruba Instant (not InstantOn) has been a simplified product line already in this respect i suppose.
Ability to configure which SSIDs are active on which AP is available in Aruba Instant (IAP) (@bcrawfo2 please note) as well as Aruba controllers. This functionality is not available in Instant On, however, as this is viewed as an enterprise feature.