Hey!
Thanks for the report, but to properly investigate your issue we need crash logs and not save games that then crashed. Those are located here C:\Users<USER>\Games\Age of Empires 2 DE\logs, also helpful would be .mdmp and log files (sync logs will have this format 140673-2021 .06.08-13.35.20-sync.txt and crash logs will be the normal logs with the date and time on the filename
Also if you want to help us further try to reproduce your crash on our
Enhanced Logging build? The steps are in this post: 📌 [HOW TO] Use the Enhanced Logging Build to generate Networking Logs (Disconnects)
That log file contains information which will help us to see exactly why the game is showing you this message, instead of the list of games.