If you need to Export a PST file and need to skip \ Ignore error with the file that can stop the migration you can add the option below to cmdlet below when exporting PST files.
-BadItemLimit 20000 -AcceptLargeDataLoss
The full cmdlet will look like this:
New-MailboxImportRequest USERID -targetRootFolder "inbox/PST" -FilePath "\\SHARE\PST\FILE.PST" -BadItemLimit 20000 -AcceptLargeDataLoss