LV - Add custom buttons to Linked variation

functions.php

<?php
add_filter( 'iconic_wlv_group_data', 'iconic_lv_add_custom_linked_variations', 10, 2 );

function iconic_lv_add_custom_linked_variations( $group_data, $product_id ) {
    // Todo1. Add the actual linked variation ID here
    $linked_variation_id = 93;
    if ( $group_data['group']->post->ID !== $linked_variation_id ) {
        return $group_data;
    }

    // Todo2: Add the list of buttons to add to the Linked Variations group.
    $to_add = array(
        array(
            'label' => 'Water green',
            'ID'    => 91
        ),
        array(
            'label' => 'Pink',
            'ID'    => 94
        ),
    );

    // ------------------------------------------------------------
    // Stop editing.
    // ------------------------------------------------------------

    $prepared_terms = array();
    foreach ($to_add as $color) {
        $url = get_permalink($color['ID']);
        $prepared_terms[$color['label']] = array(
            'label' => $color['label'],
            'current' => false,
            'url' => $url,
            'content' => "<a 
                            href='$url'
                            title='{$color['label']}' 
                            class='iconic-wlv-terms__term-content iconic-wlv-terms__term-content--link'>
                            {$color['label']}
                        </a>",
            'has_image' => false,
            'linked_variation_data' => array(
                'match' => true,
                'variation' => array(
                    'permalink' => get_permalink($color['ID']),
                    'title' => $color['label'],
                    'stock_status' => 'instock',
                    'purchasable' => true,
                )
            )
        );
    }
    
    $group_data['attributes']['pa_color']['terms'] = array_merge($group_data['attributes']['pa_color']['terms'], $prepared_terms);
	
    return $group_data;
}