Before starting, make sure you have a clean installation and avoid creating a profile until after applying the FOV and mouse smoothing fixes, as they won't work otherwise.

FOV and Mouse Smoothing Fix:
First, navigate to the game's installation folder, open the System folder, locate DefUser.ini, and open it using Notepad or another text editor.
Use the search feature to look for DesiredFOV and DefaultFOV and change the values to the FOV you want. This ini also lets you disable mouse smoothing, if you want to do that search for bMaxMouseSmoothing and set it to False.

Resolution, HUD scaling and AA fix:
Next, launch the game once and then close it to allow the XIII.ini file to be created in the System folder. Open this file with Notepad or another text editor.


Search for FullscreenViewportX and FullscreenViewportY, and set the resolution to 1280x720, as 720p is the lowest 16:9 resolution the game allows and will minimize HUD shrinking.


Afterwards, download dgVoodoo[dege.freeweb.hu], extract it somewhere on your PC and open dgVoodooCpl.exe. Leave everything in the 'General' tab at the default values except for the Output API, set that to 'DirectX12 feature level 12' and go to the 'DirectX' tab after. Here set the videocard at 'GForce 4Ti 4800', apply the max VRAM, adjust the resolution to match your monitors resolution, force 16x Anistropic Filtering and VSync, set the MSAA to 8x, untick the watermark and disable alt+enter then press apply. When that's done go into the dgVoodoo install location, MS, x86, and copy D3D8.dll. Also, copy dgVoodoo.conf which is located where dgVoodooCpl.exe is, and paste both files into the XIII System folder.




As you increase the resolution the HUD shrinks, forcing the resolution to be higher than what the game is set to in XIII.ini with dgVoodoo, will trick the game into using the 720p HUD but with a higher internal res.

720p Forced to 4K with dgVoodoo vs 4K set in XIII.ini:
This method also upscales the low res blur effects and comic panels:

Enable SSAA:
To enable SSAA with dgVoodoo, open the 'General' tab and set the scaling mode to 'Stretched, keep aspect ratio'. Next, go to the DirectX tab, set the resolution as high as your system can handle, click Apply, and copy the updated dgVoodoo.conf file into the System folder. When you launch the game, it will run at the chosen internal resolution, downscaled to your monitor's native resolution, while retaining the 720p HUD.
8K downscaled to 4K, 4xMSAA, 105 FOV, 16xAF, Fixed HUD Scaling:

If you want higher quality FMV's that are faithful to the original download this mod by RapozaDynamica. To install drag and drop the files into XIII's Video folder. This mod also comes with the intro skip.
Original vs Enhanced:
No FMV sound fix:
If the FMVs have no sound, try setting XIII.exe to Windows XP (Service Pack 3) compatibility mode and click Apply. Downloading the upscaled FMV's mod fixed this issue for me but neither methods are guaranteed. Deleting your profile by going into the XIII install folder, save and deleting XIII.pro then creating a new one also fixed it for me.