Which just lets the wizard turn the longsword as an implement. Making it fit both catagories above.
Dungeons and Dragons 4th Edition is a exception based design. Meaning that everything conforms to the way things are normally handled, in this case, all implements are one type, until they are no longer treated that way in a specific example. For instance, shifting provokes no attack from your opponent, but the Combat Challenge ability is an exception to that rule. Just like orbs, staves, rods, and other implements being treated as their own category is an exception to the rule that all implements are categorized as implements. Ordinarily, that is true, but when using Transfer Enchantment, you are limited by the specific rules of Transfer Enchantment.