Foliage PCG instances
The interaction system also works for PCG foliage. You only need to make sure that the instanced static mesh component is blocking the LookAtTrace and then you can add it to DT_InteractableFoliage as shown here How to make foliage interactable.
A good tool to generate worlds with PCG foliage is Massive World. Here is an integration tutorial of the Nice Interaction System into Massive World