Comment by wlesieutre

If you're not aware, you can remap modifier keys in System Settings on macOS. It doesn't have individual settings for left/right versions of a modifier key, so keep it in whichever mode has the modifiers on left/right paired with each other correctly, and then swap their functions to the right ones.

https://i.imgur.com/FXkmZRV.png

Settings are per keyboard so fixing your external keyboard won't mix up any other keyboards you use (particularly for laptops).