FileBot

I'm renaming some files that were already renamed by FileBot, and in the rename panel there are a number of files that have red circle X icons beside them, but the names are identical from what I can see.
There are others that have green arrows and most have no icon at all, even though the names are mostly all the same

Screenshot? Context?

The green and red icons typically indicate that a file cannot be processed due to fundamental file system limitations, e.g. likely a file already exists at the target file path, and moving forward would require FileBot to overwrite that file.