You can add up to 5 FX per clip, but they have to be different effects, meaning you can't add multiple Replace Color FX. Check and see if you can find NewBlue Color Swap and NewBlue Color Replace and add both of them to your title.
Be aware that the effects may interfere with each other, and you may have to use one particular effect first to get everything working correctly, but you can do things like this:
One thing to note is that the colors may flicker when you preview the project, but that's because PD is having to swap out the color each time a new frame appears. It shouldn't be present in the produced video.