but once the MicroSD card was replaced/reinstalled back into the phone, would the phone recognized the card & it's data..
I don't think the phone would recognize it, because when it's formatted as internal storage, it's encrypted to work with that device only. Factory resetting the phone is kind of like making it a new device, and I would think the phone would lose the encryption key along with all other data during the reset. According to
this article:
"The platform randomly generates an encryption key for each adopted device, and
that key is stored on the internal storage of the Android device. This effectively makes the adopted media as secure as internal storage. Keys are associated with adopted devices based on the adopted partition GUID. The adopted device is encrypted using dm-crypt configured with the aes-cbc-essiv:sha256 algorithm and a 128-bit key size.
The on-disk layout of the adopted device closely mirrors the internal data partition, including SELinux labels, etc. When multi-user is supported on the Android device, the adopted storage device also supports multi-user with the same level of isolation as internal storage.
Because the contents of an adopted storage device are strongly tied to the Android device that adopted it, the encryption keys should not be extractable from the parent device, and therefore the storage device can't be mounted elsewhere."