The word "most brewing" signifies a situation where something is probably going to happen or is being planned. Its antonyms can be tranquil, calm, or serene. If something is calm, then it is free from commotion or disturbance, which means that there is no brewing. Likewise, if a situation is tranquil, there is no indication of an impending event or disturbance. Serene denotes a peaceful and unproblematic ambiance that is undisturbed by brewing activities. Therefore, the antonyms for "most brewing" correspond to peacefulness, tranquility, and calmness, all of which describe scenarios that are free from brewing activities.