I am not sure about how to change colors.

But, what I do is create a custom badge and assign it to Administrators on the site.

Steps

1. Create a badge file. I have a badge file called digibit.badge that looks similar to this:
[
{
"title" : "COM_DIGIBIT_BADGES_VERIFIED_TITLE",
"alias" : "digibit-validated",
"description" : "COM_DIGIBIT_BADGES_VERIFIED_DESC",
"howto" : "COM_DIGIBIT_BADGES_VERIFIED_HOWTO",
"command" : "digibit.validated",
"extension" : "com_easysocial",
"avatar" : "images/logo--white-blue-backgroun_120x120.png",
"frequency" : 50
}
]

2. Install new badge at EasySocial | Achievements | install
3. in EasySocial Users, assign the custom badge.

Explanation about the .badge file
- The .badge file name needs to be unique to your site.
- The title, alias, and command entries need to be unique to your site.
- In our case, we made up a command because we are manually assigning the badge.
- Avatar is the path to your badge. Using a 120px by 120px png image is good.

Anyways, good luck.

I also found this which might help:

You could in the theme file code it so that it renders a unique text for users on a particular profile type. For instance, you could edit the file /components/com_easysocial/themes/wireframe/profile/default/default.php and change the codes at line 171,

I have not tested this and if possible you should not edit this page directly but override it in your theme.

[gist type="php"]
<?php if ($this->config->get('users.layout.profiletitle')) { ?>
<span>
<a href="<?php echo $user->getProfile()->getPermalink();?>" class="t-text--muted">
<i class="fa fa-shield"></i> <?php echo $user->getProfile()->get('title');?>
</a>
</span>
<?php } ?>
[/gist]

Thanks Scott, not really what I need though.

I need it to be displayed in user's streams and in comments etc so that people are aware they are talking to an Administrator.

Hey Chris,

Unfortunately that was not possible configure to show colour from your site administrator name.

Having said that, if you require us to perform the customization for you, you can always request for a quote from us at https://crm.stackideas.com and select "Customizations" . Our sales person would be glad to send you a quote for the customizations that you have requested.

By the way, thanks for sharing Scott