// woocommerce exclude category filter on all products listing page

// Add filter option to exclude products from category
add_action( 'restrict_manage_posts', 'add_exclude_category_filter' );
function add_exclude_category_filter() {
    $current_cat = isset( $_GET['product_cat'] ) ? $_GET['product_cat'] : '';
    $exclude_cat = isset( $_GET['exclude_category'] ) ? $_GET['exclude_category'] : '';
    ?>
    <select name="exclude_category">
        <option value=""><?php _e( 'Exclude category', 'woocommerce' ); ?></option>
        <?php
        $categories = get_terms( 'product_cat', array(
            'hide_empty' => true,
        ) );
        foreach ( $categories as $category ) :
            $selected = $category->term_id == $exclude_cat ? 'selected="selected"' : '';
            $current = $category->term_id == $current_cat ? 'current-cat' : '';
            ?>
            <option class="<?php echo esc_attr( $current ); ?>" value="<?php echo esc_attr( $category->term_id ); ?>" <?php echo $selected; ?>>
                <?php echo esc_html( $category->name ); ?>
            </option>
        <?php endforeach; ?>
    </select>
    <?php
}

function custom_product_query( $query ) {

    // Check if we're on the products listing page
    if ( $query->is_admin && $query->query['post_type'] === 'product' && ! is_null( $query->query_vars['s'] ) ) {

        // Check if the exclude category filter is set
        if ( isset( $_GET['exclude_category'] ) && ! empty( $_GET['exclude_category'] ) ) {
            $exclude_category = absint( $_GET['exclude_category'] );
            $tax_query = array(
                array(
                    'taxonomy' => 'product_cat',
                    'field'    => 'term_id',
                    'terms'    => $exclude_category,
                    'operator' => 'NOT IN',
                ),
            );
            $query->set( 'tax_query', $tax_query );
        }
    }
}
add_action( 'pre_get_posts', 'custom_product_query' );