Don't know if this is what you want to do or not, but you can actually change app icons for Applications however you like if you have the alternate that you want it to be.
I'll tell you how
Applications Folder (in Finder) -> Right-click on the target app -> Get Info -> Drag-and-drop the intended icon file to the top-left corner where the original icon is present.
Ik it's just a way to customise and not something official but your Mac looks the way you want it to.
Applications Folder (in Finder) -> Right-click on the target app -> Get Info -> Drag-and-drop the intended icon file to the top-left corner where the original icon is present.
Ik it's just a way to customise and not something official but your Mac looks the way you want it to.