As a plugin developer you can use this plugin as dependency of your plugin by adding a dependency tag to your POM.
To add the latest version of this plugin as a maven dependency, use the following:
<dependency>
<groupId>io.jenkins.plugins</groupId>
<artifactId>unleash</artifactId>
<version>131.v4b_705a_9b_c22f</version>
</dependency>