Really need to have Triggers in SharePoint by folder:
I would like to see additional triggers or conditions relating to this such as folder size greater than etc.
How is this not a thing?!
So I think its possible to trigger a flow when a folder is created, although slightly more drawn out than just selecting 'When Folder is Created'.
I first used 'When Item Created', and listed the document library. Then used a condition where if the 'Content Type: Name' was equal to 'Folder', it would send an email. Folder was a custom value and 'Content Type: Name' was dynamic, although I am using a 'Report library'.
This worked for me and doesn't trigger when a file is created. I had to figure it out because I was searching for ages for a 'SharePoint - When Folder Created' trigger.
Hopefully they add it soon.
I just did this and When item is created restricts you to a list.
Use When a file is created (properties only) and check the isFolder property to determine if it is a folder.
You'll need to check if the name is one of the folders you are creating and you are copying to the same site, or new folders will be created each time you create a subfolder, infinitely (or until the run limit).
There definitely needs to be a trigger for this that prevents running a new flow each time a folder is created. Its not intuitive to have to copy from site to site.