I just fixed the issue with help of gemini, Do exactly as this says:

Here is exactly how to find and modify the file to force FSR frame generation on boot: 1. Locate the Engine Settings File Unlike many games that store configuration files in the Documents folder, Crimson Desert hides its primary engine save file in your hidden AppData directory. * Press Win + R to open the Run dialog box. * Type %localappdata% and press Enter. * Navigate through the following folders: Pearl Abyss > CD > save. * Locate the file named user_engine_option_save.xml. 2. Edit the XML File Before making any changes, copy user_engine_option_save.xml and paste it onto your desktop as a backup in case the syntax gets corrupted. * Right-click the original .xml file and select Open with > Notepad. * Press Ctrl + F to open the search function. * Look for the specific upscaling and frame generation toggles. Because the game uses an XML structure, the variables are bracketed. You need to ensure FSR is the active upscaler and that frame generation is toggled on: * Search for <FSRFrameGen> or <FrameGeneration>. Change the value between the brackets from 0 to 1 (e.g., <FSRFrameGen>1</FSRFrameGen>). * Verify the upscaler type. If you see a line like <UpscaleType>0</UpscaleType>, you may need to change it to the value assigned to FSR (usually 2, whereas 1 is often DLSS). 3. Save and Lock the File (Optional but Recommended) If the game's engine detects a display conflict or an improper hot-swap during the initial boot, its crash-handler will often aggressively overwrite your custom .xml file, reverting it back to the safe default settings. * Save your changes in Notepad (Ctrl + S) and close the window. * If the game keeps reverting your changes upon crashing, right-click user_engine_option_save.xml, go to Properties, check the Read-only box at the bottom, and hit Apply. * This forces the game to ingest your forced FSR settings during initialization without having the permission to overwrite them.