Myrtle Corbin, who was born with two sets of legs, two pelvises, and two functional sets of sexual / reproductive organs. (1868-1928)
That would go to ex-England international Segar Dick Bastard. "Cigar Dick" Bastard's wiki page. https://en.m.wikipedia.org/wiki/Segar_Bastard
I do know it's not as unusual for boys to be born with multiple penises or two headed penises, but usually only one is functional and the rest is removed. Frank could bang Myrtle while they each had sex with someone else at the same time. If only pornhub was around in those days.