How to use “Out of Stock” feature

Hi,
I am testing the “Woocommerce Variations Swatches” plugin and I´d like to know if you have some demo showing how this feature “Out of Stock” works.

I loved the plugin, but I have to understand how it works to decide to buy.

I have two variations, and I need that the swatches gets blur or with a cross to show that the item is out of stock. (I send attached the address of my store)

Thanks in advance,

Luiz