Custom text output for entity reference fields
Two different options here (there are probably more!):


Use the linkit module in combination with wysiwyg and, say, the tinyMCE editor. This allows users to insert node reference links into wysiwyg text areas.
a.  Create a textfield for the link text in addition to the entity reference field.

b.  In the template file for the content type (node--CONTENT_TYPE.tpl.php), output the links manually, something like:

$path = 'node/' . $node->YOUR_ENTITY_REF_FIELD['und'][0]['target_id'];

$link_text = $node-&gt;YOUR_LINK_TEXT_FIELD['und'][0]['value'];

print l($link_text, $path);