Просто рассмотрите transform-origin:bottom left;
.elementor-image figure {
position: relative;
}
.elementor-image figure figcaption {
position: absolute;
bottom: 0;
left: 0;
transform: rotate(-90deg);
transform-origin:bottom left;
}
img {
display:block; /* to avoid white space and have a perfect alignment */
}
<div class="elementor-image">
<figure class="wp-caption">
<img src="https://picsum.photos/200/300">
<figcaption class="widget-image-caption wp-caption-text">The Lorem <span></span></figcaption>
</figure>
</div>