As found on Reddit (please note this was meant for fifa 23, replace fifa 23 by EA FC 24):
Press the Windows key + R to open the Run dialog box.
Type "regedit" (without the quotes) in the field and press Enter. This will open the Registry Editor.
Navigate to the following registry key: HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\EA Sports\FIFA 23
Look for the "Locale" key and double-click it.
Change the value to the language code of your preferred language. For example, if you want to switch to Spanish (Mexico), change the value to "es_MX".
do the same thing in "HKEY_LOCAL_MACHINE\SOFTWARE\EA Sports\FIFA 23" path.
Go back to EA App and repair FIFA 23 files and it should download the new language pack.
if you are on steam you need to change the language from steam + do these steps as well.
There are two steps to this. Worked for me.