They have researched it probably on other subjects for over 30 years. Meaning Si Yehan went to someone who's been doing research
"Ninth Master, we've already studied this project for more than 30 years. There's an enormous risk if it's done with the genetics method, but we've switched it to the method of deep hypnosis. It can accomplish the same result and absolutely won't yield any problems."
Urban · Jiong Jiong You Yao
See this! I just gifted the story: Balloon
ch 0 1 The bloodthirsty queen
Urban · Avalorian_
Uh...not exactly. Worriless Nie had a child at the age of 19 and was later turned into Ye Wanwan
"However, if we use the hypnosis method and forcefully inject someone else's memory into the hypnotized person—this action is called memory masking—then the hypnotized person will completely transform into the owner of the memory being injected. Basically, the hypnotized person will undergo drastic changes and completely turn into someone else."
Perfect Secret Love: The Bad New Wife is a Little Sweet
Urban · Jiong Jiong You Yao