To add a Sold dot over the Image, you can follow these steps:

#1. First, you add a Gallery Section

#2. Enable Gallery Captions

#3. Next, you add a SOLD text in the Description box 

#4. Add this code to the Page Header Code Injection (the page where you want to add the Sold dot)

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.7.0/jquery.min.js"></script>
<script>
$(document).ready(function(){
    $('figcaption p:contains("SOLD")').closest('figure').addClass('sold-dot');
});
</script>
<style>
  figure.sold-dot>div {
  position: relative;
  }
figure.sold-dot>div:after {
    content: "";
    display: block;
    width: 30px;
    height: 30px;
    position: absolute;
    right: 20px;
    bottom: 20px;
    z-index: 9999;
    background-color: red;
    border-radius: 50%;
}
</style>

#5. Result