One of my clients was having issues with SharePoint pages remaining checked out to editors who didn't know they hadn't published the page. They wanted to be able to remind the editors of pages they have checked out daily. The solution was to create a Flow that queried the Site Pages library, found items that had a user specified in the Checked Out to column and then sends an email. I attached the Flow export to this post.
The challenges was that the Get Files (Properties Only) doesn't return the checked out to column so I use the REST API instead but filtering on null is still not possible so it goes through all files each time. The REST API also only return the ID so I have to do another Get Item action to find the last modified by.
This could also be extended to check for draft items where the current version is not a whole number and remind users.
I know this is an old thread! i have the same request. the flow doesn't have errors in my end but it doesn't send the email alert. why do you think this happens ? or do you have any new flow that answers the same need ?