Strait of Bonifacio
Paolo Valente Poddighe is an Italian researcher who claims to have been the first to have identified Sardinia (along with Corsica) as the location of Atlantis as early as 1982. This was long before Robert Ishoy proposed the same on his website(a) and two decades before Sergio Frau published his 2002 book with an identical claim. This led to accusations of plagiarism by Poddighe, who only then published his own book, Atlantide Sardegna:Isola dei Faraoni  (Atlantis Sardinia: Island of the Pharaohs).
Where Frau locates the Pillars of Heracles at the Strait of Sicily, Poddighe opted for the Strait of Bonifacio between Sardinia and Corsica, which would imply that the islands of Atlantis ‘beyond the Pillars’ would have to be the Balearic Islands, which offer few features to match Plato’s description of Atlantis. Consequently, I am personally inclined towards siting them further east at the Strait of Messina.