Konstantin Obenland

This plugin needs Jetpack by WordPress.com to be activated and its Sharing module to be enabled. 
Enter the desired Twitter usernamen in Settings -> Sharing. It will then be appended, every time a visitor shares your content on Twitter
See the <a href="https://dev.twitter.com/docs/tweet-button" title="Tweet Button" rel="nofollow ugc">Tweet Button documentation</a> for details.
<h4>Translations</h4>
I will be more than happy to update the plugin with new locales, as soon as I receive them! 
Currently available in:
<ul>
<li>English</li>
</ul>

Jetpack Twitter Via

Adds 'via @username' to the Tweet Button provided in "Jetpack by WordPress.com"

Tanner Moushey

Jetpack is an amazing plugin with many great features. Sometimes, however, you just want to use a specific feature from Jetpack and don’t want to go through the hassle of connecting Jetpack to your WordPress.com user account. This is where this plugin comes in handy.
Just install this plugin and you will get access to all of the Jetpack modules that do not require a connection to WordPress.com.
If you find that the module you are interested in is not available after installing this plugin, that is an indication that a WordPress.com account is required for that module. These include Site stats, Publicize, and a few others.

Unplug Jetpack

Jetpack's unnecessary requirement to connect to a WordPress.com account is so frustrating. This plugin removes that requirement for all Jetpack modules that don't really on WordPress.com services.



Better than Jetpack itself!

Use Jetpack without needing to connect to WordPress.com

Jetpack Twitter Via vs Unplug Jetpack