I think such endeavors would fail: see the attempt made with Soylent.
It's easier to fast than to calorically restrict. We derive tremendous pleasure from eating. It's normal. It's a rewarding behavior to encourage our survival. Having a meal-mimicking concocting would not serve it's purpose.

Plus, when nutrients come from outside (when we eat), processes like autophagy (cell repair - renewal - cell self-eating basically) are reduced compared to fasting...

Safer, I don't know. If you purpose for safety, have a multivitamin when you fast and let your body do its thing... :)