Good News and Bad News.[br]
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Yes, it is possible to swap the logic boards of 2 iPhone XS’, '''''however''''', your pictures and other media stored on the phone is stored in a flash chip which is soldered directly onto the logic board.
Replacing the logic board outright would result in losing all the data that was originally on it. One option is to get a qualified engineer to attempt to remove the flash chip from your logic board, and resolder it to the new one. This is no easy task and the chance of it going well is not high, not to mention it wouldn’t be cheap.[br]
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Not only is this an issue, but also the front camera assembly for FaceID is locked to your original logic board and would lose FaceID if connected to a different logic board.[br]
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Many condolences for your device…