Alright so if I understand correctly, you are dynamically adding a Widget Component and want to assign your custom User Widget to it. If that is the case, try using the Widget Component’s “Set Widget” node. You can use the “Create Widget” node to create your widget and pass it on to the Set Widget node.
Also, if you are certain of the Widget class that you are going to use beforehand, then its even more easier. Just click on the Add Component node and you’ll see the details panel on the right.
From there, you can set the widget class similar to how you do it from the hierarchy.