Если вам нужен только кроспостинг из WordPress на стену группы Вконтакте без лишних и сложных настроек, то этот плагин для вас. Настройте отправку записей из WP в VK за два шага.
<ul>
<li>Автопостинг записей на стену группы Вконтакте.</li>
<li>Простая настройка в два шага.</li>
<li>Подробная инструкция по настройке в скриншотах.</li>
<li>Абсолютно бесплатный плагин, ни каких проф. и прочих платных версий.</li>
<li>Понятный код для тех кто хочет “допиливать” под себя.</li>
<li>Поддержка Woocommerce</li>
<li>Участие в проекте через <a href="https://github.com/northmule/vk-poster-group" rel="nofollow ugc">GitHub</a></li>
</ul>
Support and suggestions, <a href="https://t.me/coderunphp" rel="nofollow ugc">Telegram</a>
<h4>Sponsors</h4>
This project supports the best IDE for development <a href="https://www.jetbrains.com/?from=Original-texts-yandex-web-master-WordPress" rel="nofollow ugc">JetBrains</a>

VK Poster Group

Всё работает как надо.

Если у кого в журнале ошибка: 

{"error_code":8,"error_msg":"Invalid request: v (version) is required"

решается это добавлением строчки: $arg['v'] = '5.21';
после: $arg['access_token'] = $vkposter_token;
в файле: /wp-content/plugins/vk-poster-group/inc/vkp-function-class.php


Отличный плагин

Cross posting your entries from the Wordpress community Vkontakte Крос постинг ваших записей из Wordpress в сообщество Вконтакте

Dariusz Zielonka

This plugin was adapted to avoid loading VKontakte Community Widget JavaScripts and images in an iframe every time a page is loaded. It is a fact, that the JavaScripts and iframes increase page loading times and are often harmful for websites’ performance. Not everyone likes to have extra weight code on his/her website. Especially when functionality that is brought by the code is not essential.
This plugin is inspired by a similiar <a href="https://wordpress.org/plugins/facebook-fan-box-cache/" title="Facebook Fan Box Cache">WordPress plugin</a> and adapted for VKontakte Community Widget.
You can check post on my website – <a href="http://naturalwebdesign.net/plugins/wordpress/vkontakte-community-widget-cache/" title="VKontakte (VK.com) Community Widget Cache" rel="nofollow ugc">Natural Web Design</a>, for tutorial, updates, and news.
*** Please note, that Plugin is in BETA testing phase ***
Features:
<ul>
<li>Decrease page load time on pages that contain your VK.com Community Widget code</li>
<li>VK Cache WordPress Widget (Default 240px wide)</li>
<li>Manual Cache Refresh</li>
</ul>
A few notes about this plugin:
<ul>
<li>The plugin requires PHP5 and cURL to be installed and enabled on your server.</li>
<li>You can see a working demo of the Plugin on frontend <a href="http://deshevoperevodchikpolskiy.ru/связаться/" title="Demo on one of our Websites" rel="nofollow ugc">here</a>.</li>
</ul>
Still to be done:
<ul>
<li>Shortcode for inserting into a page</li>
</ul>
<h3>CSS Guide</h3>
If you opt to disable inline CSS, you can paste this into your themes style.css file, and it will give you the default look.
<pre><code>.widget_vkcache .community_div {
 margin:10px auto;
 width:240px;
}
.widget_vkcache .community_div_head {
 border-bottom:1px solid #D8DFEA;
 padding-bottom:5px;
}
.widget_vkcache .connections .total {
 font-size:12px;
 padding: 5px 0 0;
}
.widget_vkcache .connections .grid a {
 float:none;
 text-align:center;
 text-decoration:none;
}
.widget_vkcache .connections .grid a img {
 margin:0;
 border: 0;
}
.widget_vkcache .connections .grid a span {
 color:#808080;
 font-size:10px;
}

.widget_vkcache .img_Link {
 float:left;
 padding-right:5px;
}

.widget_vkcache .VKuser {
 padding: 3px 0;
 width: 73px;
 float:left;
 text-align: center;
}

.widget_vkcache .VKuser-pic {
 height: 47px;
 clear: both;
 overflow: hidden;
 padding-bottom: 3px;
}

.widget_vkcache .img_Link img {
 -webkit-border-radius: 0;
 -moz-border-radius: 0;
 border-radius: 0;
}

.widget_vkcache .VKusername { 
 font-size: 0.9em; 
 text-align: center; 
}

.widget_vkcache .connect_button.VKstyle { 
 display: block;
 clear: both;
 padding: 5px;
 text-align: center;
 font-weight: bold;
 font-size: 16px;
}
</code></pre>

VKontakte (VK.com) Community Widget Cache

If you want to avoid loading weighty scripts, increase your page loading speed, use this plugin to get the VK Community Widget cached.

VK Poster Group vs VKontakte (VK.com) Community Widget Cache