Did Leonardo da Vinci paint two Mona Lisas? Where are they?

There is only one Mona Lisa, at the Louvre, fully credited to Leonardo. However, there are several Mona Lisa look-alikes from his studio, some of them quite saucy. The one most similar to the Louvre one is the Prado Mona Lisa, a copy made simultaneously in Leonardo's workshop while he painted the Mona Lisa, probably made by an apprentice(s):

Source: Louvre, Paris, France.

For the one below, art experts suggest that it contains touches indicating that Leonardo contributed to it.

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Donna Nuda:

Evidently there was a market for erotic paintings. The American art historian David Brown, curator of Italian Renaissance paintings at the National Gallery of Art in Washington, has suggested that da Vinci painted a saucy parody of the Mona Lisa for his patron Giuliano de Medici, and that the Salai version is a copy.

Another version of the above exists, attributed to Salaj:

How come Taiwan is LGBT friendly, yet Japan and South Korea are not?

Source: Chantilly, Musée Condé, France.

Obviously, the original Mona Lisa also inspired some cheeky versions of her.

Source: St Petersburg. Hermitage, Russia.

Why are the people who don't support the LGBT community treated like super evil and cruel beings? People can have different opinions and thoughts on things.

Then there are the ‘meza nuda’ paintings from his workshop, often referred to as Monna Vannas.

While overall similar, there are differences in the shape of the face, the background and other details.

La Joconde nue:

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