The file which is uploaded its in the SharePoint system only right.?
If yes then - u can use the sharepoint file properties (metadata) created which stores the values of created date and time .
This is good enough to sort the records in the powerapps (for e.g this records is mapped in gallery)
Using Sort(Datasource, created, descending).
I hope this helps, if you still have any queries revert me back.
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