I have a valid save game that I created that I can’t load because it will crash AOE4 when I try to load. It will attempt to load then when the loading progress bar has got a good way through the game will exit without a trace (no error message).
I still have the save game on my machine if it would be helpful to share as an attachment.
Something to think about is the recent patch will prevent saves from the previous patch from loading. As far as I’m aware the only saves that will still load are saves of the campaign games.