Could recommend for a console hex editor under Cygwin?
There is a package called hexedit that comes up in Cygwin's package search, which I assume is a port of the same tool that is available in most Linux distributions under the same name.
I've used said utility (as installed from the Debian repositories) under Linux, and it did the job I was wanting it to do. I've not tried the version in Cygwin though so it could be a different tool with the same name.
bvi. Its home page is on sourceforge and there is a Cygwin package for it. As the name implies, its UI is very much like