If you search for on Google, you will inevitably find websites offering the file as a standalone download. Do not use these.

MT.exe is designed to work within the ecosystem of the Windows SDK. It relies on specific versions of C++ runtime libraries (MSVCRT) and other SDK components that are installed alongside it. If you download just the .exe file and drop it into a random folder, it will likely fail to run, citing missing DLL dependencies.

: Creates XML manifest files that describe an application's dependencies and security requirements.

mt.exe -inputresource:mydll.dll;#2 -out:extracted_manifest.xml

C:\Program Files (x86)\Windows Kits\10\bin\[Version]\[Architecture]