If you want to change Summary Block - Carousel Arrows to custom text, something like this.
You can use this code to Website > Website Tools > Custom CSS
/* Summary Block */
span.summary-carousel-pager-prev.previous:after {
content: "PREV" !important;
}
span.summary-carousel-pager-next.next:after {
content: "NEXT";
}
.sqs-block-summary-v2 .summary-block-setting-design-carousel .summary-carousel-pager {
width: 100px !important;
}
span.summary-carousel-pager-prev.previous:before, span.summary-carousel-pager-next.next:before {
display: none !important;
}