Is the EFV-640D-1AV automatic or quartz?

The listing says automatic, but a chronograph with a date in this line is almost always quartz. Check the caseback or the seller's spec sheet before buying if the movement matters to you.

Yes for swimming and showering. It is rated 10 ATM (100m), but there is no screw-down crown listed, so avoid diving.

What is the case size?

The listing does not give a case diameter. Edifice chronographs typically run around 44mm, so try one on if you have a small wrist.

Does the chronograph measure fractions of a second?

The listing only says stopwatch and chronograph. Most Edifice quartz chronographs time to 1/10 or 1/20 second, but confirm the exact resolution with the seller.

How does it compare with other steel Edifice chronographs?

It matches them on the basics: steel case and bracelet, mineral glass, 100m rating and a date. The black dial with mixed Arabic and index markers is the main visual difference, so pick on looks and on the movement you actually get.