Dear Fabio,
Thank you for contacting us and for using XStore.
Such cookies could be written to your headers because on one of next reasons:
1/ You have somewhere across the web-site Products element with Recently viewed products set for its Data
2/ You have Sales booster popup displayed (fake sales notification)
3/ Extra plugin writes such cookies for its reason
We can recommend you try next solution by adding the next code to your child-theme/functions.php
add_action('wp', function() {
remove_action( 'template_redirect', 'et_wc_track_product_view', 20 );
}, 70);
We can recommend you check from an incognito window or clear your browser cookies and check in non-incognito.
Otherwise, if it does not help, please, check one by one plugins you have installed and activated.
Kind Regards,
8theme team