it is not possible because the first thing is that orochimaru cant give him a saringan. As you know that the orochimaru also wanted the saringan by takeover the sasuke's body if he was able to give the saringan to tobi then he was plant saringan in his own body instead giving it to tobi
Because he isn't and uchia and it would take up to much chackra he wanted to have and uchia body.
My theory is that orochimaru knew about the evolution of the sharingan and that eventually after progressing through MS EMS it would reach the rinnegan.
now ororchimaru wanted 2 tings to learn and master every jutsu in the world and learn the secret to immortality
now just having the sahringan wont let you learn every justu because Orochimaru doesn't have all 5 chackra natures.
He knew the sharingan would eventually became the rinegan which in turn would give him access to all 5 chakcra natures + ying and yang chackra which in turn would allow him to learn and master every jutsu in the world and thus discover the secret to true immortality instead of swapping body's.
He needed and actual uchia body that can use the sharingan with no real cost as opposed to kakashi who looses great amounts of chackra using the sharingan as he isnt and uchia .