Custom WooCommerce Emails Delay

hook_queue.php

<?php

add_action( 'woocommerce_order_status_completed', 'queue_email', 10, 10 );

/**
 * Generic function that will queue any action as we see fit.
 */
function queue_email( ...$args ) {
	$filter = current_filter(); //woocommerce_order_status_completed
	$delay = false;
    
	switch( filter ) {
		case: 'woocommerce_order_status_completed';
			$delay = 2 * HOUR_IN_SECODS;
			break;
	}

	if ( ! $delay ) { return; }

	as_schedule_single_action(
		time() + $delay,
		'send_queued_email',
		[
			'filter' => $filter,
			'args'   => func_get_args(),
		]
	);
}

remove_action.php

<?php

add_filter( 'woocommerce_email_actions', 'remove_order_completed_email_action', 99 );

/**
 * Remove actions we don't want emails to trigger
 */
function remove_order_completed_email_action( $actions ) {
	$actions_to_remove = [ 'woocommerce_order_status_completed' ];
	return array_diff( $actions, $actions_to_remove );
}

send_queued_email.php

<?php

add_action( 'send_queued_email', 'send_email', 10, 2 );

function send_email( $filter, $args ) {
	\WC_Emails::send_queued_transactional_email( $filter, $args );
}