Plugins such as Divi Icons Pro, Divi Upload Icons or Divi Font Awesome does not work well with 3rd party Divi modules. You should contact the author of the icon plugin if they are willing to support Divi Supreme. They do not support 3rd party modules and that is why you’re seeing icons not rendering properly on Divi Supreme Modules. There is nothing we can do unless the plugin you using supports 3rd party divi modules. This applies to all 3rd party plugins out there.
We are also looking to add Icon Extension in the near future. So stay tuned for that!