The plugin from marketplace.atlassian.com is a plugin for Bitbucket server (formally stash) which it allows you to do the push from Bitbucket server to a Jenkins instance.
The Jenkins plugin opens a url endpoint called:
JENKINS_URL/bitbucket-hook which the Bitbucket server can do a simple
POST to the url endpoint and Jenkins will build all projects.
Both of the plugins provide the same functionality, however both come from different places. If you do not have direct access to the admin page for the Bitbucket server to install the plugin, then using the Jenkins Bitbucket plugin would be a good alternative.