This gists adds User's badges earned with badgeos plugin under his avatar in topics and replies of bbpress.

bbpress-badgeos-user-achievements-under-avatar

<?php
add_filter( 'bbp_get_reply_author_link', 'my_append_badges_via_filter', 10, 2 );

function my_append_badges_via_filter($author_link = '', $args) {

	# Needed to get the user ID of the person intended to be displayed.
	$user_id = bbp_get_reply_author_id( $args['post_id'] );
	#Construct your output here.
	$badge_output = '';


	$achievements = badgeos_get_user_achievements( array( 'user_id' => $user_id ) );
	if ( !empty( $achievements ) ) {
			$badge_output .= '<div class="achievements">';
        foreach ( $achievements as $achievement ) {
						if($achievement->post_type != 'badges')
							continue;
            $badge_output .= '<div class="achievement achievement-' . $achievement->post_type . '">';
            //echo '<h2>' . get_the_title( $achievement->ID ) . '</h2>';
            $badge_output .= get_the_post_thumbnail( $achievement->ID, 'thumbnail', array('title'=>get_the_title( $achievement->ID ) ) );
            //echo __( 'Earned on: ', 'text-domain' ) . date( get_option( 'date_format' ), $achievement->date_earned ) ;
            $badge_output .= '</div>';
        }
			$badge_output .= '</div>';
  } 
		
	return  $author_link . $badge_output;
}