[knc1]

No one can say without the individual test results.

The general problem is you will have to deal with the information stored in the eMMC outside of the file systems that is device specific.

We have a thread here on replacing the eMMC (with a larger capacity model).

Here you are talking about removing and then re-using BGA devices, not an easy task because the used part has to be re-balled.

Better to just buy new eMMC devices (perhaps of a larger capacity to make them more attractive on re-sale) and replace the faulty ones.

And you will still have to find a way to read-out the device specific information from the 'bad' devices so that you can transfer that information to the replacement device

Such "test jigs" do exist, since in manufacturing the eMMC is programmed before being soldered in place on the board.
But they are not cheap, nor easy to make.