No. Vivo Y83 has 2 slots dedicated for SIM card and a separate slot for the MicroSD card. You can expand phone storage by up to 256GB with the help of the memory card.
Yes, Vivo Y83 does have the AI Face Beauty which detects gender, age, skin tone, skin texture and lighting environment and applies the necessary corrections on your selfies. You also have the option to in-active it.
Yes, Vivo Y83 does have the power saving mode.
No. Vivo Y83 does not have the dual camera setup. It has a 13MP rear camera and 8MP front camera.