Hey,
if anyone still needs help for this problem, I might have something for you. Had the same problem and the solution were two simple settings that had to be adjusted in the EngineFixes.toml file, as mentioned in this reddit post:
Summary:
Set...
SaveGameMaxSize = true
MaxStdio = 8192
...and your done.
These are experimental, but seem to work fine. No problems so far on my end. If you don't have the mod Engine Fixes already installed, I highly recommend downloading it. It is a very powerful tool and bigger modlists are basically unthinkable without it. This did the job for me, maybe it helps you too.