Q: How do you keep files updated when consultants prefer to use Dropbox, but you’re managing everything in Sharepoint/OneDrive?
A: Use Microsoft Flow to create a link between folders.
You need to be able to login to both Dropbox and your Microsoft account (portal.office.com)
In portal.office.com, select Flow
In Flow, Create from template. You can search for a template like –
Copy files between Dropbox and SharePoint
And just use the folder and arrow icons to browse to your source and destination folders.
Select Edit in advanced mode to create additional conditions (specify file type, etc.).