Hopefully this helps someone in the future! I had to look all over for these.
Hopefully this is allowed
WINDOWS LTSC SHA-256 CHECKSUMS Compiled from: https://my.visualstudio.com/downloads
WINDOWS 10 LTSC File name: en-us_windows_10_enterprise_ltsc_2021_x64_dvd_d289cf96.iso SHA256: C90A6DF8997BF49E56B9673982F3E80745058723A707AEF8F22998AE6479597D File name: en_windows_10_enterprise_ltsc_2019_x64_dvd_5795bb03.iso SHA256: B570DDFDC4672F4629A95316563DF923BD834AEC657DE5D4CA7C7EF9B58DF2B1 File name: en-us_windows_10_iot_enterprise_ltsc_2021_x64_dvd_257ad90f.iso SHA256: A0334F31EA7A3E6932B9AD7206608248F0BD40698BFB8FC65F14FC5E4976C160 File name: en_windows_10_iot_enterprise_ltsc_2019_x64_dvd_a1aa819f.iso SHA256: 0ACB0766F0591FE917E00BA8EB2FBDD32A36A2345492191E0376130A45974795 WINDOWS 11 LTSC File name: en-us_windows_11_enterprise_ltsc_2024_x64_dvd_965cfb00.iso SHA256: 157D8365A517C40AFEB3106FDD74D0836E1025DEBBC343F2080E1A8687607F51 File name: en-us_windows_11_iot_enterprise_ltsc_2024_x64_dvd_f6b14814.iso SHA256: 4F59662A96FC1DA48C1B415D6C369D08AF55DDD64E8F1C84E0166D9E50405D7A


fyi it’s on massgrave’s faq section here
Note that their key for win 10 ltsc does not activate windows. It won’t work for me
you mean the serial key on their website? it’s an “install key” officially provided by microsoft, essentially a dummy key to fill as a placeholder (on unattended installs mostly)
you should use the MAS script and use its HWID or TSForge option, it should work.