If you need to deploy to many offline PCs, consider setting up a local or using Microsoft Endpoint Configuration Manager to distribute language packs.
dism /online /Add-Package /PackagePath:"C:\offline_lp\Microsoft-Windows-Client-LanguagePack-Package~31bf3856ad364e35~amd64~ja-JP~.cab" windows 11 language pack download offline
dism /online /Add-Package /PackagePath:"C:\offline_lp\Microsoft-Windows-Client-LanguagePack-Package~...~[LANG-TAG]~.cab" If you need to deploy to many offline
If you need to deploy to many offline PCs, consider setting up a local or using Microsoft Endpoint Configuration Manager to distribute language packs.
dism /online /Add-Package /PackagePath:"C:\offline_lp\Microsoft-Windows-Client-LanguagePack-Package~31bf3856ad364e35~amd64~ja-JP~.cab"
dism /online /Add-Package /PackagePath:"C:\offline_lp\Microsoft-Windows-Client-LanguagePack-Package~...~[LANG-TAG]~.cab"