WPForms smart tags inside checkbox labels

functions.php

<?php
/**
 * Process smart tags inside checkbox choice labels,
 *
 * @param array $field
 * @param array $deprecated
 * @param array $form_data
 * @return array
 */
function wp_checkbox_choices_process_smarttags( $field, $deprecated, $form_data ) {

	foreach ( $field['choices'] as $key => $choice ) {
		if ( ! empty( $choice['label'] ) ) {
			$field['choices'][ $key ]['label'] = apply_filters( 'wpforms_process_smart_tags', $choice['label'], $form_data );
		}
	}
	return $field;
}
add_filter( 'wpforms_checkbox_field_display', 'wp_checkbox_choices_process_smarttags', 10, 3 );