Easiest way to handle ordering on Event Hub on Blob Containers

I am looking for an easy solution for ordering events.

I have an Azure blob storage where an external service push files into a container with different subfolders. 

I want to respond to event by creating a handler on Event Hub on: Create blob for those files, but those files should be processed in a specific order, so files in folder-1 should be processed before folder-2 and then folder-3.

The problem is the external service just upload files in whatever order, and those files might be big.

So the file in folder-3 might load first, and then file in folder-1 which might be big so it might take 40 seconds to upload, and then  file in folder-2.

What the easiest way (without writing code if possible)?

Is there a way in Event Hub , or any other Azure service (if possible without writing code) to send to the subscriber in a custom order?