Build a calendar that fits your world! Whether you're a GM just here to track your Forgotten Realms campaign with a preset calendar, or a fanciful world-builder with 12 moons (Like Eberron's) and zany timekeeping systems to match, we've got you covered.
From the perspective of the southern hemisphere, the moon phases appear to move in the opposite order than they do from the northern hemisphere. I'm afraid that, without the option to reverse the moon phases, any fantasy worlds with that perspective have to use custom phases in order to make the phases progress "normally."
There's also just the simple benefit to having that customization because there's no reason why a moon couldn't rotate in the opposite direction to our own moon anyway, so having the ability to reverse the moon phases even from the perspective of the northern hemisphere is still a perfectly reasonable request.
From the perspective of the southern hemisphere, the moon phases appear to move in the opposite order than they do from the northern hemisphere. I'm afraid that, without the option to reverse the moon phases, any fantasy worlds with that perspective have to use custom phases in order to make the phases progress "normally."
There's also just the simple benefit to having that customization because there's no reason why a moon couldn't rotate in the opposite direction to our own moon anyway, so having the ability to reverse the moon phases even from the perspective of the northern hemisphere is still a perfectly reasonable request.