Either way, check that both `\Documents\Larian Studios\Baldur's Gate 3\Mods` (if the directory exists) is empty, and that there are no folders in `\Steam\steamapps\common\Baldurs Gate 3\Data` (or similar install paths depending on platform) other than "Localization" on both of your machines.
In the launcher (or main menu), compare game versions to make sure you're both on the same version of the game.
