Change image on post title hover (more than one instance) – Jquery

I think you could the code working, if you used the current term as the selector as there’s only one featured image and multiple links for each term.

For example, first add the term to the image classes,

<img class="img-fluid ga-img ga-img-<?php echo $term->slug; ?>" src="https://wordpress.stackexchange.com/questions/366314/<?php echo esc_url($ga_url);?>">

Then add the term to every post link,

<a href="https://wordpress.stackexchange.com/questions/366314/<?php the_permalink( $post->ID ); ?>" data-swap="<?php the_post_thumbnail_url($post->ID,'full'); ?>" data-term="<?php echo $term->slug; ?>" >
    <?php echo $post->post_title; ?>
</a>

Now you should be able to use the term as selector in jQuery,

jQuery(document).ready(function () {

  jQuery('.ga-links a').hover(function() {
    var currentTerm = jQuery(this).data('term'),
        swapImage = jQuery(this).data("swap");
    jQuery('.ga-img-' + currentTerm).attr('src', swapImage);      
  });

});