Hi @Alex Miles
Welcome to Q&A forum ~
But please note, tag "office-onedrive-client-itpro" focuses more on general issue of OneDive, such as deployment, installation, and troubleshooting like file synchronization.
As your issue need the code help, I would suggest you post a new thread on following forums.
OneDrive Developer
OneDrive developer community
Besides, I find a similart thread "Copy Content Of a Folder to Another SP Online Folder", PnP PowerShell command "Copy-PnPFile" seems to be possible to copy files. But at current time, I do not find the command to capture the action of creating a new folder to trigger the copy command.
Hope the infromation could be helpful to you.
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