Hi Ismael,
Yes, it works – thank you so much!!

Hey!
Thanks for your answer.

I worked on this and now i have a different solution:
i created a custom field (with ACF) “product_url” and edited the masonry_entries.php like this
instead of line 734:
$this->loop[$key]['url'] = get_permalink($id);

i have:

if(get_field('product_url',$id)){
$this->loop[$key]['url'] = get_field('product_url',$id);
} else {
$this->loop[$key]['url']= get_permalink($id);
};

This works pretty well.
Now my question is: how can i hook this snippet into my childtheme?
(i know i can’t just overwrite masonry_entries.php because it only works with template files – so there has to be some kind of hook… but i can’t get it!)

Thanks for your help!!