I do not have the graph @Kulkul can provide the above if he wish.
I have a topic Load multiple Families from a folder and to multiple Revit Models from a folder
The OP topic are similar in the end as he wants after he figures out the graph for the open delete and save (which @Kulkul has already proven possible) he wants to run it on multiple revit files on a given folder. My topic from the above link has the dyn in which i think you also made a comment.
Again automating or automation is at the moment not possible unless someone out there is not yet sharing. All the comments from @Andreas_Dieckmann @erfajo @john_pierson are on the topic. It might help to understand the issue why.
Thanks