What you may see listed as an ETA 2813 clone, is not actually an ETA clone at all. In fact, there is not an ETA 2813 to clone. It is also not an ETA 2824-2 clone.
The caliber 2813 is closer to being a Miyota 8215 clone, although there are some notable differences.
Caliber 2813 is a Chinese movement, apparently produced by several factories such as Dixmont in Guangzhou (also Mingzhu, Nanning NN2813, Beijing). This explains why the caliber number is often written as DG2813.