Most of the EASYSIGHT frame can be ordered as sunglasses. You can check this option under the description of each frame.
Yes Sure ! you can order sunglasses with your prescription. You can select sunglasses and then go to select lens option and then select prescription lens know more
Photochromic lenses automatically gets darken when exposed to UV rays outdoor and turn back to clear when comes back to indoor.
If your sunglasses are non-prescription sunglasses then it will be thin but if your sunglasses are prescription sunglasses then it depends upon your prescription and lens index.
EASY SIGHT offers best tint for your prescription sunglasses you can learn about tint here.
Yes , But with some specific frames you can get clip-ons.