How to Prevent Products from Being Sold Outside Mix and Match Bundles
TL;DR: To sell a WooCommerce product only inside a Mix and Match bundle, edit the product and tick Not sold separately on the Inventory tab. The setting is built into Mix and Match Products 2.9.0 and newer, so there is nothing extra to install. The product’s Add to cart button disappears on its own page, replaced by the message “This product can only be purchased as part of a mix and match bundle.” and links to the bundles that include it, but the product stays fully selectable inside any Mix and Match container.
