I have always had a gripe about the lack of an easy way to work with templates in WorkFlowy.
In DL, at least there is a Ctrl-Drag.
But I hope you are considering more than that - at least a normal copy-paste, in addition to “move item”?
With the Ctrl-Drag option I believe it is not possible to copy to another document? Mostly one would have templates separate from the work documents.
Even if they were in the same document, it would easily be in the “opposite end” of the document, thus a very long “drag”.
Copy-paste would at least make it practical.
(An additional, more advanced feature would be to be able to drag an entire document (from the list on the left) into a position in the current document. This way, one could have a folder just for snippets like this.
Absolute top of the line would of course be if there was a right-click option “paste from template” and one would then get the list of snippets from such a designated template folder.
But just copy-paste would at least make it “realistic” to work with.