Gen 1 and Gen 2 super mutants retain their primary sexual characteristics so unless the Enclave scientists who further enhanced Frank decided to do further modifications I'd assume he still has whatever original equipment down there.
Also I was just referring to non Transhuman characters, Cain and Tanya are some of the only ones I can think of that aren't beyond human in one way or another, which for reference would include Jedi. Funny enough while it's not focused on the Biologis faction of the Mechanicus could maybe do genomic level modifications on baseline humans and given how the average tech priest looks I wouldnt be surprised if they swapped their biology around for fun once in awhile.