Hello over here 
I’m watching the UE4 trello roadmap from time to time and I have recently found that the “Prefab” task was gone?
I’m talking about fully customizable child blueprints components Prefabs.
Is that ever going to happen? Because I feel like it’s a pretty mandatory feature for a SDK.
Have a good afternoon
Well there are other entries are gone with the last update 
We still plan to support ‘templates’ for ChildActorComponents to allow customizing the Child Actor that is spawned. That is tracked by this entry:
Sorry it doesn’t really give better info, we’ll fix that. This work is currently scheduled for 4.14, but as always, things can change.
James
Thank you for this information! This feature will open up much more capabilities in UE4 without the need of a constructor script or C++!!!