WooCommerce Exclude On Sale Products from Shop Page https://wpsites.net/?p=114677

WC Exclude On Sale Products Shop Page.php

add_action('pre_get_posts', 'wc_exclude_sale_items_from_shop_page');
function wc_exclude_sale_items_from_shop_page($query) {

    if ( is_admin() || ! $query->is_main_query() ) {
        return;
    }

    // Check if it's the main shop page
    if ( is_shop() ) {
        $query->set('meta_query', array(
            array(
                'key'     => '_sale_price',
                'compare' => 'NOT EXISTS',
            ),
        ));
    }
}

WooCommerce Exclude On Sale Products from Shop Page.php

// Add the following code to your theme's functions.php file or a custom plugin.
add_filter('woocommerce_product_query_meta_query', 'woo_exclude_sale_items_from_shop_page');
function woo_exclude_sale_items_from_shop_page($meta_query) {

    if ( is_admin() || ! is_shop() ) {
        return $meta_query;
    }

    $meta_query[] = array(
        'key'     => '_sale_price',
        'compare' => 'NOT EXISTS',
    );

    return $meta_query;
}