Je te mets ce message que j'avais vu sur Reddit, ça avait marché pour un utilisateur. Si jamais tu testes, j'aimerais bien avoir ton retour :
Update your graphics card drivers to the latest version from the graphics card manufacturer's website. Make sure to do a clean install (or reinstall) of these drivers to reduce the potential of conflicting configurations.
Update your Windows Operating System using Windows Update. Make sure to install any optional updates as these aren't installed automatically.
Disable any overlays (Geforce Experience, Discord overlay, etc.) that may be present while playing the game. Also make sure to close any other programs that are running alongside the game while playing.
Make sure that any anti-virus software you have has the appropriate exceptions for the game's install folder.
Perform a clean boot. To do this for Windows 8/10: Open the Task Manager and select the 'Start Up' Tab. disable everything here and restart the PC. For Windows 7: Click Start, type 'msconfig.exe' in the Start Search Box, then press Enter to start the System Configuration utility. On the General tab, click the Selective Startup option, and then click to clear the Load Startup Items check box. On the Services tab, click to select the Hide All Microsoft Services check box, and then click Disable All.
En gros : mets à jour ton GPU, soit sûr que l'installation des drivers est clean. Mets à jour Windows. Désactive les overlay comme Geforce experience, Discord. Ne fais rien tourner autour. Mets des autorisations dans l'anti-virus pour KH.
Puis si rien ne marche dans tout ça, tente un lancement minimal de Windows :
https://support.microsoft.com/fr-fr/topic/proc%C3%A9dure-d-ex%C3%A9cution-d-un-d%C3%A9marrage-en-mode-minimal-dans-windows-da2f9573-6eec-00ad-2f8a-a97a1807f3dd