Hey there @Rhys5
As you mentioned, one solution is to create a local component only to test a new “list item” and duplicate its instance. But it might be cool if we had a way to make a design pattern, just like components.
This is also achievable with “placeholder components”. it’s not a tool, but an approach. you create a component containing some smaller “placeholder component”, that can be replaced by other components. a “placeholder component” is like an empty frame with some unnatrual border color. just to make it noticable that it’s only a placeholder, not a real component for design system. and with the “instance property” you can easily swap it with the desired component.
For repetitive things like list-items, you can also check this post:
Vote for that one if you believe it is the same as your idea. That one has more votes.