Froggynet.com's What is your Pirate Name? Is also a mapping generator. You enter name and gender, and when you repeat the entry, the results are the same. They have some historical names sprinkled in, including some not from pirate history. However, their titles are a bit tongue in cheek, and as are their nicknames, and the selection of personal names had a few that were thrown in for laughs. However, some of the names I tried were also a little mischievous. My suggestion, when using this generator, is to try varying the names you enter until you find one you'd like to use.
Rebecca Scudder, my name, gave me the pirate name of Capn Wong the Twitchy Wench. Perhaps the less said about that the better. Henry Johnson rejoices in the name Tom Long Arse. The mapping is more than basic substitution, because combinations of the names did not result in repeats of any part of the name. So Rebecca Johnson was Captain Chaste Heart, Henry Scudder was Lackey

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Sylvester the Bastard, Henry Smith was Admiral Drake, Mary Smythe was Jacquotte the Brown.
After settling that first and last names didn't bring up the same result, I just tried a variety. Wendy Jones was Aetheflaed the Fierce. Paul Atreides was First Mate Pegleg Stubble. Harry Potter became Commodore James the Long Eye and George Williams was Arthur Treacher the Drunken. My next tries resulted in Rebecca Williams as Capn Jacquotte the Gold Toe, Miles Davis as Commodore Pink Eye, Rebecca Davis as Admiral Esmerelda, and George Peterson serves on ship as Castaway Francis.
It looks like there are only so many titles that they can give out, although not all names get titles. There is some repetition of nicknames, and possibly fewer female names than male, although my sample is not large. Miles will probably want to try again, and so, perhaps, does George Williams, since he is in the business of slinging canon balls, not fried fish. As you can see from the variety, there are a few historical pirate name elements dropped in, but most of the names are widely varied and occasionally ridiculous. Still, some of them would be quite dis-respectful pirate names.
Pirate names from Stupidstuff.org
Pirate names at Stupidstuff.org also deserves a mention. It asks you for your first and last name, but not gender. Repeating the names gives the same answer, making it a mapping generator.
Rebecca Scudder is Red Stefan, and Henry Johnson now Lord Cruikshank. Rebecca Johnson became Mad Ned The Executioner, Henry Scudder was Black Bill, and finally, Peter Jones should be known as Long Dong Silver.
All of my tries resulted in male names, but no repeat names.