my $t= XML::Twig->new( pretty_print => 'indented',
                    twig_handlers => {
                          'product'=>sub{  
                                              my @pname = $_[1]->get_xpath('name');
                                              my @pids = $_[1]->get_xpath('product_id');
                                              
                                              print $pids[0]->text," - ",$pname[0]->text,"\n";
                                              my %h;
                                              
                                              my @ids = $_[1]->get_xpath('attributes/attribute/group/id');
                                              my @names = $_[1]->get_xpath('attributes/attribute/group/name');
                                              @h{map {$_->text} @ids } = map {$_->text} @names ;


                                              my @vids = $_[1]->get_xpath('attributes/attribute/value/id');
                                              my @values = $_[1]->get_xpath('attributes/attribute/value/value');
                                              @h{map {$_->text} @vids } = map {$_->text} @values ;

                                              print map {"\t$_ - $h{$_}\n"} keys %h;
                                              print "\n\n";
                                             

                          }
                    }
);
$t->parse($xml);


####OUTPUT
ABC123 - My product
         - 12.1998
        1561 - Lġngd (i mm)
        1507 - Engines
        1498 - Year model
        12033 - Vehicle equipment
        12019 - Maybe
        1518 - Year model (to)
        301 - Generator


XYZ789 - My product
         - 12.1992
        1507 - Engines
        1498 - Year model
        1518 - Year model (to)
        301 - Generator