You’d have to edit the php file for the plugin. Simple switch, but you’d have remember what you did and manually update the plugin whenever updates are available.
At around line 85, you’d want to basically move the block of code below wherever inside the li tag with the class cat-post-item.
<?php if ( $instance['date'] ) : ?>
<p class="post-date"><?php the_time("j M Y"); ?></p>
<?php endif; ?>
so you’d end up with something like this:
[Code moderated as per the Forum Rules. Please use the pastebin]
That should work. You could also probably use CSS absolute positioning to move stuff around, that way you aren’t messing with the hard code of the plugin. But that can get messy, and I’m not sure everything inside the list item elements have CSS selectors assigned.