The plugins are different!
The first plugin “pdf24-posts-to-pdf” integrates a small box into the sidebar of wordpress to export multiple articles to pdf. You need a little bit more time to install this plugin, because you have to put some piece of code into the wordpress sidebar template.
The second plugin “pdf24-post-to-pdf” integrates a small box underneath each articles in he blog. Only one articles can be exported to pdf. The installation is much easier as the first plugin, because the wordpress plugin system is used.
So the plugins are not really the same, but both are for exporting articles to pdf.
