unfortunately I havnt implemented anything like this...
but you could export your favorites to a file then manually edit the file and re-import. Its pretty simple:
export your favorites (using the little heart icon in the bottom of the window)
open up the exported file with TextEdit
the file will look something like:
"Safari" : [
just change Safari to Safari TP, your file should now look like this:
"Safari TP" : [
re-import back into Cookie, once again using the little heart icon.
Importing the new file will ADD to any favorites you already have, so you won't lose any of your current favorites