How do I get two codes (macro) to run alternately (with one macro)

Thanks for providing the script @Min_Kyu_Kang,

I see from the code that you're using mouse and keyboard simulation which is the least stable way to control an app with SoundFlow. It's always best to use UI automation wherever possible.

With that said this one required some more complex logic to get it working but Here is a script that should do what you're after.

function toggleRxOutputGain() {
    // Activate iZotope RX's main window
    sf.ui.izotope.appActivateMainWindow();

    const iZotopeMenuName = sf.ui.izotope.childrenByRole("AXMenuBar").first.children.find(mi => {
        return mi.title.invalidate().value.startsWith("iZotope RX")
    }).title.invalidate().value;

    // Open Preferences Window
    sf.ui.izotope.menuClick({ menuPath: [iZotopeMenuName, "Preferences…"], });

    const preferencesWindow = sf.ui.izotope.windows.find(win =>
        win.childrenByFullRole("AXWindow:AXDialog") &&
        win.title.invalidate().value === "Preferences"
    );

    // Wait for Preferences window
    preferencesWindow.elementWaitFor();

    // Get the Output Gain slider
    const outputGainSlider = preferencesWindow.getFirstWithDescription("Output gain [dB]");

    // Get the current gain value
    const currentGain = outputGainSlider.value.doubleValue;

    // Function to set the Output Gain slider
    const setOutputGain = (gain) => outputGainSlider.value.value = String(gain);

    // If the Output Gain is set to 0.0 set it to 6.0, if it is not, set it to 0.0 
    if (currentGain === 0) {
        setOutputGain(6.0)
    } else {
        setOutputGain(0.0)
    }

    // preferencesWindow.windowClose(); Remove the "//" at the start of this line if you want the preferences window to close.
}

toggleRxOutputGain();

I hope that helps. :-)