The TitleBlacklist extensions allows creating a blacklist with strings, to block page creation when these match the page title. Nevertheless users with special rights (e.g. Admins) can create those pages anyway, but instead get a warning text, that they are about to create a page with a blacklisted part. See screenshot:

Since moving pages with blacklisted titles will also be available for admins in the FileImporter we should show a similar warning at some place on the page. Question is where and how.