"no less famous" is correct and can be used in written English.
It is typically used to emphasize the fame of something or someone, often in comparison to something else. Example: Although she was the youngest sister in the family, she was no less famous than her older siblings.
In the next room, featuring "Americans in Florence," we encounter Sargent's self-portrait, donated to the Uffizi in 1906, his no less famous portrait of his friend Henry James, and his likeness of the (English) writer Vernon Lee, a long-term resident of Florence and friend of both the painter and James.
Einstein's disagreement with the Copenhagen school came to a head in the famous exchange with Bohr at the fifth Solvay conference (1927) and in the no less famous Einstein, Podolsky, Rosen paper of 1935.
No less famous a designer than Calvin Klein showed a version of them earlier this month in Milan.
Pinter is no less famous for his dramatic silences and for the most astute use of the theatrical pause since the heyday of Jack Benny.
It is perfectly plausible that as a basketball player or even as a swaddled halfback he would have been no less famous and quicksilver.
It is hard to protest in the winter, when no less famous an American than George Washington thought it was a good time of year to retreat and wait for spring.
So far, they've included Ariel Pink, Odd Nosdam, Jello Biafra, and Japanther, as well as a few less famous but no less notable characters, like Alan's own mom and dad, and a homeless guy he met in the park.
Sutherland is the London-born son of legendary Canadian actor Donald Sutherland and less famous but no less accomplished Canadian actress Shirley Douglas (he has a twin sister, Rachel).
No less than France's most famous thespian Gerard Depardieu has returned to portray big, dumb loveable Obelix who fell in the magic potion as a baby.
My own favorite peace symbol was designed specifically for the purpose like Holtom's emblem, and is less famous, but no less eloquent.
Everyone knows about the Big Four – New York, London, Milan and Paris – but as soon as Anna Wintour completes her biannual pilgrimage jetting between those front rows, a second wave of less famous (but no less fascinating) fashion weeks kick off.
