DOWNLOAD LINK: NX-Game-Icon-Customizer.zip
Note: Make sure to install Sys-Tweak first before using this tool... Instructions can be found at:
https://github.com/hotshotz79/NX-Custom-Game-Icons
or
https://gbatemp.net/threads/custom-game-icons-tutorial-and-sharing-hub-no-forwarders.574675/