wordpress hide related products when upsale has been added code example
Example: remove upsell products woocommerce
remove_action( 'woocommerce_after_single_product_summary', 'woocommerce_upsell_display', 15 );
remove_action( 'woocommerce_after_single_product_summary', 'woocommerce_upsell_display', 15 );