VueJS 2调用WordPress/WooCommerce API遇CORS错误求助

本地通过vue-cli-service运行VueJS 2应用，使用axios调用WordPress/WooCommerce REST API时，始终出现以下CORS错误：

Access to XMLHttpRequest at 'https://woocommercewebsite.com/wp-json/wc/v3/products/categories/' from origin 'http://localhost:8080' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: It does not have HTTP ok status.

目前可以正常调用其他REST API，但唯独WooCommerce的API无法调用。已尝试以下两种解决方案，但均无效：

尝试方案1：在WordPress主题functions.php中添加CORS头部 #

function add_cors_http_header(){
    header("Access-Control-Allow-Origin: *");
    header("Access-Control-Allow-Methods: POST, GET, OPTIONS, PUT, DELETE");
    header("Access-Control-Allow-Credentials: true");
    header('Access-Control-Allow-Headers: Origin, X-Requested-With, X-WP-Nonce, Content-Type, Accept, Authorization');
}
add_action('init','add_cors_http_header');

尝试方案2：在Nginx虚拟主机配置文件中添加CORS头部 #

add_header "Access-Control-Allow-Origin" "*";
add_header 'Access-Control-Allow-Methods' 'GET, POST, PUT, PATCH, DELETE, OPTIONS';

在Postman中可以看到响应已包含设置的CORS头部，但错误依然存在。已尝试StackOverflow上的相关方案，均未解决问题。了解过代理方案，但由于需要调用多个不同的REST API，且服务器为远程主机，该方案不适用。

内容的提问来源于stack exchange，提问作者John