We Are Volume

Post Sync Manager lets you move posts between your local, staging, and production WordPress sites with a single click — directly from the Gutenberg editor.
Free features: 
* Push and pull posts, pages, and custom post types between environments 
* Sync status indicator (in sync, remote newer, local newer, conflict) 
* Secret-key authentication between sites 
* Full sync log with pagination
<a href="https://postsyncmanager.com" rel="nofollow ugc">Pro version</a> features: 
* Bulk sync page with per-row push, pull, and status check
<h3>External Services</h3>
This plugin communicates only between your own WordPress sites when pushing or pulling posts. No data is routed through any third-party server.
<ul>
<li>What is sent: post content, post meta, and media attachments belonging to the post being synced</li>
<li>Where it goes: directly to the remote WordPress site URL you configure in Settings</li>
<li>Authentication: requests are authenticated with a secret key you set — no external accounts required</li>
</ul>

Volume Post Sync Manager

Push and pull individual posts between WordPress environments.

PiotrPress

Clearcode

This plugin allows you to deploy your WordPress site source code from git repository using webhooks.
Automatically pull from a repository to a web server. You can configure which branch is triggering the pull action. 
After each deployment plugin saves the status to logs which are available through wp-admin and also are sent by email.
Supported git repository hosting services: 
* <a href="https://github.com/" rel="nofollow ugc">Github</a> 
* <a href="https://bitbucket.org/" rel="nofollow ugc">Bitbucket</a> 
* Stash

CC-Deploy

This plugin allows you to deploy your WordPress site source code from git repository using webhooks.

Volume Post Sync Manager vs CC-Deploy