lightsystem

The plugin is configurable letting you define what feeds to read and how often to read them. It also lets you decide whether you want to store the external images locally, inserting them into the media gallery, or otherwise simply hotlink them (that is the default).
You will find these settings in your administration page on the Settings->RSS Settings sub-menu.
Check out the <a href="https://github.com/LightSystem/WordPress-Plugin-RSS-Sync" rel="nofollow ugc">project on GitHub</a>.

RSS Synchronisation

Use this plugin if you wish to read external RSS feeds into WordPress posts.

Scriptonite

This is a simple yet powerful plugin to repair your wordpress RSS feed. This plugin will help you if you get an error that looks similar to this:
XML Parsing Error: XML or text declaration not at start of entity 
Location: http://www.yoursite.com/feed/ 
Line Number 2, Column 2: 
-^
If you get this error and have not been able to resolve your feed issues than this plugin is what you need. RSS repair adds a new item to your wordpress tools menu. After you do a core update or theme update and your feed stops working, apply the fix and your feed will be as good as new.
Code sources from: http://wejn.org/stuff/wejnswpwhitespacefix.php.html

Fix My Feed RSS Repair

This is a simple yet powerful plugin to repair your wordpress RSS feed. This plugin will help you if you get an error that looks similar to this:

RSS Synchronisation vs Fix My Feed RSS Repair