hi @nounouno5402
Windows 11 does not be default install keyboards, not even installing UK Keyboard! and I am using a default version (en-gb).Version
This means Unreal 5 crashes because yours is a Japanese version and probably you dont have both Japanese keyboard installed this is what my Settings looks like.
Windows 10 used to install the UK keyboard automatically. but the Windows 11 DOES
There is an article about the problem
Install a language for Windows - Microsoft Support
Here is my Windows 11 showing that even my UK keyboard is not installed.
This picture shows the Japanese keyboard for me to install.
For your version you need to install probably the US Keyboard for (en-US) and en-gb)
When I entered this Time and Language page all the keyboards and language drivers had to be downloaded.
You will probably need to download the English-US language pack as well to see the keyboard drivers.
Overriding language with editor language configuration option (en).
Unreal 5 does not check that the (en) drivers have been loaded
Using OS detected locale (ja-JP).
Have to tried setting Unreal Language to Japanese? .
Many people use this setting
Maybe ask in the Japanese forum
スウェーデンからこんにちは！ - International / 日本語 (Japanese) - Epic Developer Community Forums (unrealengine.com)