If the SD card is in the tablet, then you wouldn't need to download to it first and then transfer to the tablet. And, even if you did, it would not move them to the tablet. Part of them would stay on the card, so then you couldn't remove the card from the device, as that is the original location of the app. Which, would mean the card would have to have been encoded to accept apps and would only work with the device that you did the encoding through. So if you made those changes to the card while it was say in that tablet, no other device could read or access the card.
Are you trying to download the apps through some other device and then move them over to the tablet?