This lens is equipped with an A bayonet. The 7iii is, as far as I know, a full-frame system camera. So it has an E bayonet. Furthermore, this lens is designed for C-sensors. But your camera has a full-format sensor.
To cut a long story short: No - it doesn't fit!
However, Sony has brought suitable lenses onto the market with the new release of the 7 series.