July 2018
Played ME1 and ME2 on my Xbox One because why not and they came with the gamer pass. Got newer xbox cause also why not lol. Go to play ME3 and importer finds no saves. Wtf. Go to ME2, no saves found. Double wtf. ME1 has save. Kill Saren again, reload ME2. Still no saves but finds ME1 character in importer. Settle with what I got and attempt to play ME2 AGAIN. Get all the way to character customization and I get a message about "data waiting to upload from another xbox" message. What's going on and how do I fix it
July 2018
Looks like a problem that is discussed for a different game in this thread at the MS forum.
This is not a problem with the game but with your Xbox, so if the solutions provided in the linked thread don't helps, you have to contact XBox support.