woocommerce-subcategories.php

<?php

add_action( 'woocommerce_before_shop_loop', 'metaltrade_categories', 5 );
function metaltrade_categories(){

    global $wp_query;
    if( empty( $wp_query->queried_object->term_id ) ){
        $parent = 0;
    } else {
        $parent = $wp_query->queried_object->term_id;
    }
    $args = array(
        'taxonomy' => 'product_cat',
        'hide_empty' => false,
        'parent' => $parent
    );
    $terms = get_terms( $args );

    if( !empty( $terms ) ){
        
        echo '<ul class="products columns-4 cat-term-wrap">';

        $i = 1;

        foreach( $terms as $term ){

            $link = get_term_link( $term->term_id, 'product_cat' );

            $thumbnail_id = get_term_meta( $term->term_id, 'thumbnail_id', true );
            $image = wp_get_attachment_image_url( $thumbnail_id, 'thumbnail' );
            if( !empty( $image ) ) {
                $class = 'term-image';
            }else{
                $class = 'term-noimage';
            }

            echo '<li class="category-loop product">';
            	echo '<a href="' . $link . '">';
            		if( !empty( $image ) ) {
	                	echo '<img class="category-loop-thumbnail" src="' . $image . '" alt="' . $term->name . '" />';
            		}
                	echo '<h3 class="' . $class . '">' . $term->name . '</h3>';
            	echo '</a>';
            echo '</li>';

        }

        echo '</ul>';

    }

}

?>
      
<style>
.cat-term-wrap {
    width:100%;
    padding:0;
}
.category-loop a{
    display:flex;
    align-items: center;
}
.cat-term-wrap .category-loop .category-loop-thumbnail{
    width:50px;
    margin-bottom:0;
}
.cat-term-wrap .category-loop h3{
    padding:0 10px 0 10px;
}
</style>