+1 here, been developing Shopify for nearly 10 years I can tell you this settings would have come in handy plenty of times. We always provide an accompanying text field to provide the variant ID or SKU along with the product, but this is not great UX.
Topic summary
Request for a Shopify theme section “schema input” that allows selecting specific product variants (e.g., size/color) directly in the theme editor.
Current status: Shopify staff confirm no variant input exists in the documented input settings and have logged a feature request. No timeline or further update was provided.
Workarounds: Developers commonly add a text field to enter a variant ID or SKU alongside product selection, but note this is poor UX and error‑prone.
Community feedback: Multiple +1s from experienced theme developers and merchants, stressing the need for variant-level selection, especially for custom themes that display products by variant.
Suggestions: Introduce a “variant_lists” schema input to enable selecting variants rather than default/first_available.
Technical note: “Schema input settings” are theme editor configuration fields; current docs are linked and show no variant input type.
Outcome: No resolution; the request is acknowledged and remains open pending future updates.