How can i change sort category view starting from child then parent, not alphabetically

To sort hierarchically, try adding a sorting function to your functions.php (or plugin).

// This will sort and place everything in the $into array
function sort_terms_hierarchically(Array &$cats, Array &$into, $parentId = 0) {
    foreach ($cats as $i => $cat) {
        if ($cat->parent == $parentId) {
            $cat->posts = array();
            $into[$cat->term_id] = $cat;
            unset($cats[$i]);
        }
    }

    foreach ($into as $topCat) {
        $topCat->children = array();
        sort_terms_hierarchically($cats, $topCat->children, $topCat->term_id);
    }
}

Now on the display side, you could grab all of your categories and display them with the parent name second.

$terms = get_the_terms( $product->get_id(), 'product_cat' );
if ( $terms ) {
    $listItems="";
    $sortedTerms = array(); // empty array to hold the sorted terms
    sort_terms_hierarchically( $terms, $sortedTerms ); // sort everything
    foreach( $sortedTerms as $parent) {
        if ( empty( $parent->children ) ) continue;

        foreach( $parent->children as $child ) {
            $listItems .= '<li>' . $child->name . ', ' . $parent->name . '</li>';
        }
    }
}

// Display the list
if ( !empty( $listItems ) ) {
    echo '<ul>' . $listItems . '</ul>';
}

Hope this better answers your question!