WooCommerce: How to Programatically Set Product Variation Attributes as Product Taxonomy Attribute Items?

I am looking for a way to programmatically set product variation attributes on a WooCommerce product using product attribute taxonomies instead of custom attributes. I understand this is the traditional way to set custom values:

$variation->set_attributes( 
	array( 
		'Format' => 'Hardcover',
		'Condition' => 'New' 
	)
);

However, I don't want to set custom product attributes. I want to set the product variation attributes as existing product attributes taxonomy values like so:

$variation->set_attributes( 
	array( 
		'pa_format' => $woo_product_meta['format'] // this is a string equal to 'Hardcover',
		'pa_condition' => $woo_product_meta['condition'] // this is a string equal to 'New'
	)
);

This syntax does not work. I am using product attribute taxonomies as my product attributes like so:

// Set product attributes
$attributes = array();

// add the format attribute
$attribute = new WC_Product_Attribute();
$attribute->set_id( wc_attribute_taxonomy_id_by_name( 'pa_format' ) );
$attribute->set_name( 'pa_format' );

// get existing configured terms programatically
$attribute_format_terms = get_terms( array( 'taxonomy' => 'pa_format' ) );
$attribute_format_term_id = false;
foreach ( $attribute_format_terms as $term ) {
	if ( $term->name == $woo_product_meta['format'] ) {
		$attribute_format_term_id = $term->term_id;
	} 
}
$attribute->set_options( array( $attribute_format_term_id ) );
$attribute->set_position( 0 );
$attribute->set_visible( true );
$attribute->set_variation( true );
$attributes[] = $attribute;
				
// add the condition attribute
$attribute = new WC_Product_Attribute();
$attribute->set_id( wc_attribute_taxonomy_id_by_name( 'pa_condition' ) );
$attribute->set_name( 'pa_condition' );
// get existing configured terms programatically
$attribute_condition_terms = get_terms( array( 'taxonomy' => 'pa_condition' ) );
$attribute_condition_term_id = false;
foreach ( $attribute_condition_terms as $term ) {
	if ( $term->name == $woo_product_meta['condition'] ) {
		$attribute_condition_term_id = $term->term_id;
	} 
}
$attribute->set_options( array( $attribute_condition_term_id ) );
$attribute->set_position( 1 );
$attribute->set_visible( true );
$attribute->set_variation( true );
$attributes[] = $attribute;
				
$product->set_attributes( $attributes );

And in this case, $woo_product_meta['condition'] and $woo_product_meta['format'] both return strings from a form input. Condition will either be 'New' or 'Used' and Format will either be 'Hardcover' or 'Paperback'. My desired outcome is to have this code:

// create product variation
$variation = new WC_Product_Variation();
$variation->set_parent_id( $product->get_id() );

$variation->set_attributes( 
	array( 
		'pa_format' => $woo_product_meta['format'],
		'pa_condition' => $woo_product_meta['condition'] 
	)
);

Work in a way that sets the product variation attributes to their respective WooCommerce product attribute taxonomy values. For example, if $woo_product_meta['format'] is equal to 'Hardcover', then the script should access the configured terms for 'pa_format' and set the product variation attribute for pa_format equal to this value. Same thing for Condition.

I've tried everything and even used AI to help to no avail. I'm not entirely sure I am asking the right questions and providing the correct details, so please let me know if you need clarity and additional information. Thank you so much for your help in this matter!

Finally found a solution to this and I want to share it in case it helps someone else in the future.

It is essential to get your attribute taxonomy (the one assigned to your parent product) using the following:

$term = get_term_by('name', $taxonomy_item_name, $taxonomy);

Then, when setting your variation attributes, it is essential to not use the term name ($term->name) or ID ($term->term_id) and instead use the slug ($term->slug), like so:

$variation->set_attributes( 
	array( 
		'pa_format' => $term->slug,
		'pa_condition' => $term->slug
	)
);

Every online forum and documentation piece I could find made it clear that only the ID or human-readable name will work, but in my case, neither worked, and both returned (in the debug log):

PHP Warning: Undefined array key "{term name or ID}" in /wp-content/plugins/woocommerce/src/Internal/ProductAttributesLookup/LookupDataStore.php on line 459

So after testing the slug on a whim, I realized it works perfectly for this case. Using the slug is also true when trying to set default attributes for a product. Here is the working code to achieve that:

$product->update_meta_data( '_default_attributes', array( 'pa_taxonomy' => $term->slug ) );

Hope this helps!