Как вариант в файле /catalog/view/javascript/common.js вставить код
localStorage.setItem('display', 'list');
перед
// Product Grid
$('#grid-view').click(function() {
// What a shame bootstrap does not take into account dynamically loaded columns
cols = $('#column-right, #column-left').length;
if (cols == 2) {
$('#content .product-list').attr('class', 'product-layout product-grid col-lg-6 col-md-6 col-sm-12 col-xs-12');
} else if (cols == 1) {
$('#content .product-list').attr('class', 'product-layout product-grid col-lg-4 col-md-4 col-sm-6 col-xs-12');
} else {
$('#content .product-list').attr('class', 'product-layout product-grid col-lg-3 col-md-3 col-sm-6 col-xs-12');
}
localStorage.setItem('display', 'grid');
});
if (localStorage.getItem('display') == 'list') {
$('#list-view').trigger('click');
} else {
$('#grid-view').trigger('click');
}