ethereal,
Dilettante_Pro, или так...
<div class="swiper-pagination swiper-pagination-fraction">
<div>
<span class="swiper-pagination-current">1</span>
<span class="swiper-pagination-total">5</span>
<span class="swiper-pagination-all">12</span>
</div>
</div>
<script>
for(const element of document.querySelectorAll("span"))
element.textContent = element.textContent.padStart(2, "0");
</script>