Confusing

DAF HASHAVUA (Shabbos 81b) part # 2 Rashi quotes from the תשובת הגאונים. "On Erev Rosh Hashana they swung the new bean plant 7 times around the head of the child and said זה חליפתי etc. Afterward the plant gets thrown into the river". The מגן אברהם (O. Ch 605) writes that this Rashi  (תשובת הגאונים) is the original מקור (source) for כפרות as we know it today. The original Minhag of כפרות was solely for the protection of the children that they shouldn't die.  HOW DOES כפרות PROTECT FROM DEATH? We find in the גמרא the concept of confusing the Satan (כדי לערבב השטן) We also find a similar case of שינוי השם changing the name of a חולה. (sick person) The original Minhag of כפרות was also the same idea. It was done for the protection of the children that if there was ח"ו a גזירה for the זרע (child)  to die we confuse the שטן with a different זרע (seed) the bean plant which gets thrown in the river. At a later stage when the Minhag כפרות started for adults, they wouldn't use the flower pot with bean זרע. They used instead a גבר (chicken) to confuse the שטן so not the גבר the man will die but the גבר the chicken. The יעב"ץ writes, he doesn't understand why the use of female chickens for females. Hens (female chickens) are not called גברת. אמבצי