Let's compare a little more closely—we wouldn't want to tear down a stunt double by mistake. That's the Mi Watch on the left, Apple Watch Series 5 on the right.

It’s the slight differences that give away the Mi Watch:

A boxier, edgier case, screen, and "digital crown"

A wider black bezel around the display, and a taller profile to match

Charging contacts on the rear, and flappy protruding mounts for the detachable band.