You can use Ultimate Filter & Search app https://apps.shopify.com/ultimate-search-and-filter-1 that has built-in feature to display variants as single products. It allows you to show variants by any options (color, material, custom option, i.e case type, phone, frame). One advanced feature is showing the matching variant image with filter selection and search term.
The demo store: https://usf-horizontal.myshopify.com/collections/shirts
Filter or Search by Red color will show up product variant image in red.