#1. Suppose we have a category with this URL, and we need to add some text under the Candles category title.

and text under the Blown Glass category title.

and text under the Talavera category title.

#2. Use this code to Code Injection – Footer

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.7.0/jquery.min.js"></script>
<script>
  $(function() {
  var loc = window.location.href; // returns the full URL
  if(/candles/.test(loc)) {
   $('<p class="custom-text">My dad once told me, laugh and the world laughs with you, Cry, and I&apos;ll give you something to cry about you little bastard! We gotta burn the rain forest, dump toxic waste, pollute the air, and rip up the OZONE!</p>').insertAfter('h2.nested-category-title');
  }
     if(/blown-glass/.test(loc)) {
   $('<p class="custom-text">They&apos;re using our own satellites against us. And the clock is ticking. My dad once told me, laugh and the world laughs with you, Cry, and I&apos;ll give you something to cry about you little bastard! You really think you can fly that thing? Life finds a way.</p>').insertAfter('h2.nested-category-title');
  }
     if(/talavera/.test(loc)) {
   $('<p class="custom-text">Drive us out of here! Checkmate... Life finds a way.</p>').insertAfter('h2.nested-category-title');
  }
});
</script>
<style>
p.custom-text {
    text-align: center;
    border-bottom: 1px solid rgba(0,0,0,0.2);
    padding-bottom: 20px;
    margin-bottom: 40px !important;
}

h2.nested-category-title:after {
    display: none;
}
section:has(.custom-text) h2.nested-category-title {
    padding-bottom: 0px !important;
    margin-bottom: 0px !important;
}
</style>

#3. Result