r-a-y

By default, any member on your BuddyPress site is allowed to send private messages to anyone in your userbase.
This plugin only allows friends and site administrators to send private messages. Thus, acting as another deterrent from illegitimate users.
<h3>Donate!</h3>
I’m a forum moderator on the buddypress.org forums. I spend a lot of my free time helping people – pro bono!
If you downloaded this plugin and like it, please:
<ul>
<li><a href="https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=CT8KZGFEVA3R6" rel="nofollow ugc">Fund my work soundtrack!</a> Music helps me help you! A dollar lets me buy a new tune off Amazon MP3, Amie Street or emusic.com! Or if you’re feeling generous, you can help me buy a whole CD! If you choose to donate, let me know what songs or which CD you want me to listen to! 🙂</li>
<li>Rate this plugin</li>
<li>Spread the gospel of BuddyPress</li>
</ul>

BuddyPress Private Messages for Friends Only

This plugin only allows friends and site administrators to send private messages on your BuddyPress site.

Shamim Hasan

Front End PM extension to integrate with WooCommerce. User can contact seller directly from product page. Option to set so that user can contact seller only after purchase.
<a href="https://wordpress.org/plugins/front-end-pm/" rel="ugc">Front End PM</a> 
<a href="https://wordpress.org/plugins/woocommerce/" rel="ugc">WooCommerce</a>
This two plugins need to be activated first before activating this extension.
Once activated, user can send message to seller directly from product page. 
You can go to Dashboard > Front End PM > Settings > Misc > WooCommerce to set if you want your users can contact seller only after purchase. You can also set in which order statuses customer can contact seller.
<a href="https://www.shamimsplugins.com/docs/front-end-pm/integration/front-end-pm-woocommerce-integration/?utm_campaign=wordpress&utm_source=readme&utm_medium=description" rel="nofollow ugc">More Details</a>
Github
<a href="https://github.com/shamim2883/front-end-pm-woocommerce-integration" rel="nofollow ugc">https://github.com/shamim2883/front-end-pm-woocommerce-integration</a>

Front End PM – WooCommerce Integration

This is very helpful plugin to integrate with Front End PM and WooCommerce. Users can ask pre-sale question or seller can provide support after purchase within wordpress.

Nice plugin to integrate with Front End PM and WooCommerce

User can contact seller directly from product page. Option to set so that user can contact seller only after purchase.

BuddyPress Private Messages for Friends Only vs Front End PM – WooCommerce Integration