Similar to this post but not quite, I have a Wordpress theme with free Fontawesome already installed and I wish to add a field in the "create Categories" box where I could type in and choose an icon to assign to each CPT's taxonomy. Such a field was available in another theme but not on this one where I do have the possibility to add icon but from the media library instead. Is there a way to add it? Some snippet?

UPDATE: I found exactly the plugin that does the work, however it showed a problem: it doesn't output the icon because the theme function to pull the image from media library seems to take priority. The question is if there's a filter to eliminate that theme function (given the fact that I need to find where it is nested)