Very little of it would work as written, even if we make modern extrapolations and assumptions. Some of it would be interesting, though. I doubt iot would have much of an impact. Most of his designs were not the inspirations of a solitary genius, but variations on themes that engineers and artists were playing with, but couldn't quite get to work. I've seen sixteenth and seventeenth century toys in museums - multiple-shot field guns with cranked magazines, revolver rifles, multibarrel pistols with rotating barrel arrangements... they all look incredibly cool, and didn't work well or reliably enough to make it into mass production. That will likely be the fate of da Vinci's inventions, too.