The phrase "most swishing" typically refers to something that moves through the air with a soft, rustling sound. Synonyms for this term might include "swooshing," "swishing," "whispering," "whooshing," and "rustling." Each of these words conveys a slightly different nuance, with "swooshing" suggesting a slightly faster and more forceful motion, while "whispering" implies a more delicate and subtle sound. "Whooshing" might be used to describe something moving through the air quickly, while "rustling" tends to suggest a softer, gentler sound. Depending on the specific context, any of these synonyms might be an effective alternative to "most swishing".