We have upgraded a dev database for Oracle 12c to Oracle 19. We did this by creating a new pluggable database and using the data pump to migrate the data over. Then we give the new database the original database's TNS name and rename the old database. All of our existing connection files appear to be working fine. Is there any need to recreate them?
Also, I noticed that this still appears to be an issue at ArcGIS 10.6
https://support.esri.com/en/technical-article/000011653