There is this engine based example, though I don’t think there is an editor based project:
I have an example project of mine based on that one, sharing: PlayCanvas | HTML5 Game Engine
Is it recommended to use batching and hardware instancing together for optimisation?
I’d say it depends on your scene, but never on the same exact model. Use instancing when using lot’s of instances of the same model + material.
Batching may work better for objects that use a different model but the same material, it can group them into a single draw call. Though batching has a generation cost, it takes time to process the objects so you can’t easily add/remove objects.
Whereas with instancing that is mostly free.