Implement product variations (colour swatches) & Quick add feature

General information for the website: We sell organic and fair trade children's clothes
Kind of development: Customization of existing website
Description of requirements/features: Many of our item styles come in different colours. We need to implement a colour swatch feature on the category, and the product pages so that customers can easily identify and select the alternative colours for a certain style. We have tried implementing this using various plug-ins but they do not seem to offer all the features we need. Some do not allow us to properly track the SKU’s in the product pages, others don’t show the swatches in the category page

The second task we need is for the implementation of a Quick add feature on the Category page that allows a customer to select a colour swatch and a size, and add it to their basket without leaving the Category page
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