How to copy a node with all the details

My requirement is that I should have two trees that on the right side it should show the explorer and on the left side, I should have a zip file structure.

based on the number of the items in the drive, I load the data into my tree directory by directory. therefore in my right tree, I don't have the full list of all the items in the tree node until user clicks on all the nodes.

Now my problem is that I need to drag and drop a node from the Explorer tree to the zip tree but my node in the explorer tree didn't populate with all the nodes. I would like to check what is your suggestion and How I can handle this situation?

I tried to create my nodes when user click on the node and when he wants to drag it but it doesn't give good user experience since system need to load all the folders and files under that folder.

Please take note that drag and drop is working fine and I am using below events for doing it.

private void tree_MouseDown(object sender, System.Windows.Forms.MouseEventArgs e){
}

private void tree_DragOver(object sender, System.Windows.Forms.DragEventArgs e)
        {}

private void tree_DragDrop(object sender, System.Windows.Forms.DragEventArgs e)
        {}

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