You can use Child Actor Components to add blueprints inside of other blueprints, this allows you to have different interaction options depending on what Child Actor Component the player is looking at, even if those Child Actor Components are in the same blueprint. To add a Child Actor Component just copy the video below.
When you add a Child Actor Component to the actor you can select it and in the details panel set the Child Actor Class, this is where you set the blueprint you want to use. Once you set this you should see the blueprint you set appear in blueprint viewport and you can use it like any other component such as set the location and rotation and change its settings.
For this to work the blueprint you are adding the Child Actor Components to must NOT have the BP_SGKInteractionInterface set in its Implemented Interfaces in its Class Defaults and can NOT have its own interaction setup. It must also not have any collision that could block the Interaction trace from hitting your Child Actor Components!
So as an example if you where setting up a car to have different interaction options depending on the door the player is looking at, you would have separate blueprints for each door, with each door blueprint having its own interaction setup like shown in the video below. Then using the Child Actor Component you would add the door blueprints to your main car body blueprint, but you car body blueprint must NOT have its own interaction options or have the BP_SGKInteractionInterface set in its Implemented Interfaces in its Class Defaults. If it does the interaction setup in your door blueprints won’t will not work!
Any of the blueprints you use with the Child Actor Component must be setup like a normal interaction actor, for more info on setting up an interactive actor watch the video linked below.