Sort product by popularity with price greater than zero

class-wc-query.php

add_action( 'woocommerce_product_query', function( $qeury ) {
    if ( empty( $qeury->query_vars['orderby'] ) || 'popularity' !== $qeury->query_vars['orderby'] ) {
        return;
    }

    add_filter( 'posts_clauses', function( $args ) {
        $args['orderby'] = ' CASE wc_product_meta_lookup.min_price WHEN 0 THEN 1
            ELSE -1
            END ASC, wc_product_meta_lookup.total_sales DESC, wc_product_meta_lookup.product_id DESC
        ';

        return $args;
    } );
} );