debman
Read man pages from uninstalled packages.
TLDR
Read a man page for a command that is provided by a specified package name
$ debman -p [package_name] [command_name]
Specify a package version to download
$ debman -p [package_name]=[version] [command_name]
Read a man page in a .deb file
$ debman -f [path/to/filename.deb] [command_name]