For additional security, the suggestion is made to move the wp-config.php up one level. Can this be done after the site has already been launched? Any potential issues in doing this? Are there an restrictions/suggestions on what the new folder should be called?
You can safely move it as far as I know.... but what do you mean folder?
Up one level would already be a folder....
if your site is in html, or public_html or whatever, you place the wp-config file in whatever folder holds your html or public_html folder
like if your path is /home/content/u/s/e/user/html/
And your WP is in html, the wp-config would go in user, the next folder up which is not web accessible. WP will automatically look for it there
If you are on shared hosting, you probably can't do that anyway
And if you have WP in a subdirectory, there would be no point in moving wp-config, as moving it up a level would still put it in a web accessible directory
You can safely move
No (that I can think of).
You should not create any new folders. Simply move file up one level. For example if your current path is