Unitys Prefab Equivalent in Unreal or similar or how do I make some specific kind of object?

Here’s a link to another post that states that this feature is missing and will most likely be never resolved.

https://forums.unrealengine.com/t/how-to-access-exposed-variables-of-a-child-actor-component-via-the-details-panel/327959/13

In my view this makes implementing modular actors much harder and time consuming.