I flew one not long ago ICN-NRT and the closet didn't look different from those on mainland 738s, but of course I did not measure the dimensions. It was definitely smaller than the original CO 737 configuration that had stowage for 2 carts, an IFE closet and a larger coat closet in that space forward of 2AB.

OTOH, 3AB had more legroom than 3EF, owing to the much deeper recline of 2AB. 2AB also sits farther back from the bulkhead to accommodate the legrest. I believe 2AB is the same type of seat Copa has on their newer 738s. Worth noting that neither 2AB nor 3AB have screens (though they only display a map and the stored DTV content).

FWIW...