I am trying to set an image before woocommerce's breadcrumb. I tried everything but I can't find the correct file to mod. I can do it also with js, but the image has to come by wp backend.
Try this hook:
add_action( 'woocommerce_before_main_content', function() {
echo '<img src="your-image.jpg">';
}, 18, 0 );
Read the source code for best documentation: templates/archive-product.php