Thiev: If you installed the game in Program Files (default location), saves will probably be in:
C:\Users\<username>\AppData\Local\VirtualStore\Program Files\GOG.com\Divine Divinity
I have the "Divinity: Original Sin - Enhanced Edition" 2.0.119.430 game installed in the folder of my choice. Microsoft Windows 10.0.19042.1165. The game has two dozen saves, they are loaded regularly. The %USERPROFILE%\AppData\Local\VirtualStore\ folder is empty. The Program Files\GOG.com\ folder does not exist. There is a Games folder in the folder where the GOG Galaxy app is installed, but it's empty. On the C drive, there are generally only three places where there are folders with the name "savegames": "C:\Program Files (x86)\Ubisoft\Ubisoft Game Launcher\", "C:\ProgramData\sangFroidData\" and "%USERPROFILE%\AppData\Local\". None of them does not apply to this game.
They would still be in the install folder (..\Divine Divinity\savegames). Right click a shortcut for the game, select Properties, then in the Shortcut tab, click the 'Open File Location' button.
There are only three folders in the folder where the game is installed: "Data", "Shipping" and "The Divinty Engine Enhanced Edition". In the third of these, only "platforms".