Quick tutorial to enable in-game setting changes.
I found that the windows defender is the culprit. It forbids you from changing the in-game setting by reverting back to previous setting. It’s not the cloud saves nor OneDrive, but anti-virus who locks the game from writing/editing the setting file.
Solution: Add the ‘Grim Dawn.exe’ under “Allow an app through Controlled Folder Access” which is found beneath Ransomware Protection in Settings. Check which exe your steam using, either the x86 (in GD folder) or x64 (in GD\x64 folder).
Happy grinding and farming in Cairn, folks.