wpler

<a href="https://www.wpler.com/linkmanager-fur-multisites/" rel="nofollow ugc">Deutsche Beschreibung des Plugins</a>
You run a Multisite Blogsystem with open registration for users to add own blogs and their can using a theme by 
different installed themes, but you want to show a link into the footers of the themes but only once time and for 
every blog another one?
With this plugin you can manage your outgoing links into the themes by a shortcode/function for every blog. You can 
set for every link the target, relation (Attribute rel), linktext and -title and the target url. Also you can set more 
than one link for a blog.
For output you can use a shortcode or a function . This function get the links 
for the current blog-id and printed this, if links are available.
All options/links can set by network admin only. The outputs needs no capability.

WPMU LinkManager

Manage your Themes footer links for every blog into a multisite includes with conditional tags.

Glamdea

Remove the footer of your theme and hide all credits links. Just install and activate the plugin and you’re done. No complicated settings or extra steps to do. 
Note: Once you activate the plugin, you might need to clear your cache in order to see the results, if you dont have a cache plugin you can always download one. 
Please have a look on the following websites to see an example on how your footer might look like after using our plugin: 
<a href="https://glamdea.com/" rel="nofollow ugc">Glamdea</a> 
<a href="https://dubaislawyers.com/" rel="nofollow ugc">Dubai’s lawyers</a> 
<a href="https://eventmanagement.cateringindubai.com/" rel="nofollow ugc">Event Management Dubai</a>

Remove Footer Credits & Powered By

In just one click hide all credits links in your footer. Just install and activate the plugin and that's it.

WPMU LinkManager vs Remove Footer Credits & Powered By