Hope, The following code solve your problem. Add this in functions.php
$tags = $_GET['taxonomy'];
$taxonomy_name = array('product_tag','product_cat');
if (in_array($tags, $taxonomy_name)) {
add_action("{$tags}_edit_form_fields", 'form_fields', 10, 2);
}
function form_fields($term, $taxonomy){
?>
<tr valign="top">
<th scope="row">Description</th>
<td>
<?php wp_editor(html_entity_decode($term->description), 'description', array('media_buttons' => false,'quicktags' => false)); ?>
<style>
.js .tmce-active .wp-editor-area{
color:black !important;
}
</style>
<script>
jQuery(window).ready(function(){
jQuery('label[for=description]').parent().parent().remove();
});
</script>
</td>
</tr>
<?php
}