We have not tried mixing the night before, but I think it would probably work! (acouplecooks.com)
I recommend mixing it the night before and storing in the refrigerator as it didn't have a great consistency when just soaked for the suggested 3 minutes. (amazon.com)
You can always prepare quinoa cakes and an eggplant mix the night before and just heat it in the morning. (pearltrees.com)