Why not drag the widget's blueprint at runtime?

Hello!
That is quite the astute question. “Why not” indeed.
In fact, you can!
Reading your post, it looks like you are referring to widget operations and I may have a bit of documentation for you to look over if you wish to do so.

Behold! Drag and Drop operations!

If I am mistaken, feel free to reply and I will continue to assist you to the best of my abilities.

I hope this documentation serves you well.