Add -Directory and -File switch parameters to Copy-Item, just like Get-ChildItem.
A -File switch would make it possible to avoid copying empty folders. Also, in some situations (see [question posted on StackOverflow](https://stackoverflow.com/questions/48026637/powershell-copy-item-doesnt-copy-when-filter-is-used/48026959?noredirect=1#comment83054046_48026959) getting the desired result requires Convert-Path | Copy-Item, but then "already exists" errors arise due to copying the folder multiple times. A -Files switch would avoid those errors. (Currently, you'd have to add -Force if you want to suppress the errors.)
A -Directory switch would provide an equivalent to xcopy /T.