Hi,
There is no option to have the compare feature in modules.
You could activate it changing the line:
if(hikashop_level(2) && hikaInput::get()->getVar('hikashop_front_end_main', 0) && hikaInput::get()->getVar('task') == 'listing' && $this->params->get('show_compare')) { ?>
in product/listing.php and the line:
if(hikaInput::get()->getVar('hikashop_front_end_main', 0) && hikaInput::get()->getVar('task') == 'listing' && $this->params->get('show_compare')) {
in product/listing_img_title.php
However, the system doesn't support several listings on the same page. So if you have several products listings on the same page, it wouldn't work properly. So I would recommend to change the code only if you know PHP/JS so that you can fix what won't work properly.