If you want to create new items in a Playlist without having to add them to the Presets library first you can do the following...
1. On the Playlist page tap the '+' button in the top right.
2. Choose "Duplicate Item With New Name". This will create a copy of whatever is loaded and let you give it a new name.
The new item will appear in the Playlist but it won't be added to the Presets library.
If you later want to make this available in the Presets library you can load it (tap it in the Playlist) then tap the Disk icon on the main metronome page and choose "Copy to Preset Library"