If you want to customize the pagination text under the Posts list on the Posts Archive (“Newer Posts / Older Posts”) and don’t use Beaver Themer, you can use gettext as it’s a translatable text:
function my_text_strings( $translated_text, $text, $domain ) {
switch ( $translated_text ) {
case '« Newer Posts' :
$translated_text = __( '« New text for Newer Posts', 'fl-automator' );
break;
case 'Older Posts »' :
$translated_text = __( 'New text for Older Posts »', 'fl-automator' );
break;
}
return $translated_text;
}
add_filter( 'gettext', 'my_text_strings', 20, 3 );
If your site language is not EN, replace the strings to customize — Newer Posts
and Older Posts
by the one provided in your language.
Also, gettext can be used more largely to customize any translatable text.