Yes, though he writes this to Voltaire in 1759. (In the 1730s, he'd been been a romance in art anti in his correspondance with him.) Apropos Racine's play about Titus and Berenice, his favourite. Note that something Caesar & Cleopatra as well as Titus & Berenice have in common is Roman ruler & foreign Queen (resented by Romans), but as opposed to Antony & Cleopatra not in a way where the Roman is presented as losing all for love. (Never mind history, I'm just talking tropes here.) Titus and Berenike give each other up for duty and rulership. Caesar doesn't give up Cleopatra per se but he leaves again for his life in Rome. All very Aeneas and Dido, and of course we had Fritz quoting Dido to Voltaire in his indignant 1743 letter, as spotted by you, casting himself as Dido. So I think it's not out of the question the whole love across the border, duty vs romance set up resonated with him.
Re: Pharsalus - he used that comparison to Mitchell as well, for one of the 1757 battles - "my Pharsalus against the House of Austria". (Err. Six more years to go, Fritz.) There's certainly a high degree of fascination with Caesar in general, see also ranting to Wilhelmine in his sour Grapes letters to Italy of how Caesar would despise today's Italians (before admitting he's the Galley slave scorning the free).
But the thing is - if an opera is supposed to celebrate Fritz the conquering hero over a powerful woman, well, you know what's right there? Alcina. Ahem. Also, it's not like Fritz was subtle with his allegories otherise. Even the starry-eyed editor mentions he - of course just as an ironic jest - had the field preacher preach about St. Paul's "Women be silent" after Mollwitz. So picking an opera in which the most famous (at this point) Queen of the ancient world - "non humilis mulier", as even Horace, otherwise writing Augustan Propaganda, put it - plays a positive role and ends up with more, not less power, is actually downright layered for what might or might not be going on in his subconscious.
(BTW, also had a look at some more of the many political letters to Heinrich, and when Heinrich after the Joseph meeting speculates that maybe a new relationship with the Austrians could be a thing Fritz is all "then the Queen-Empress" (not the Queen of Hungary!) "would have to give up the habit of hating me which she has kept for thirty years" first. Fritz pretending to be baffled at MT having anything against him is Fritzian, but what slays me is when his biographers - or editors like even Mitchell's - follow suit.)
(Not to mention that Fritz writing to Heinrich, of all the people, how anyone could have a grudge against poor him is hilarious for other reasons.)
Re: "Hot or not" in 1742
Re: Pharsalus - he used that comparison to Mitchell as well, for one of the 1757 battles - "my Pharsalus against the House of Austria". (Err. Six more years to go, Fritz.) There's certainly a high degree of fascination with Caesar in general, see also ranting to Wilhelmine in his sour Grapes letters to Italy of how Caesar would despise today's Italians (before admitting he's the Galley slave scorning the free).
But the thing is - if an opera is supposed to celebrate Fritz the conquering hero over a powerful woman, well, you know what's right there? Alcina. Ahem. Also, it's not like Fritz was subtle with his allegories otherise. Even the starry-eyed editor mentions he - of course just as an ironic jest - had the field preacher preach about St. Paul's "Women be silent" after Mollwitz. So picking an opera in which the most famous (at this point) Queen of the ancient world - "non humilis mulier", as even Horace, otherwise writing Augustan Propaganda, put it - plays a positive role and ends up with more, not less power, is actually downright layered for what might or might not be going on in his subconscious.
(BTW, also had a look at some more of the many political letters to Heinrich, and when Heinrich after the Joseph meeting speculates that maybe a new relationship with the Austrians could be a thing Fritz is all "then the Queen-Empress" (not the Queen of Hungary!) "would have to give up the habit of hating me which she has kept for thirty years" first. Fritz pretending to be baffled at MT having anything against him is Fritzian, but what slays me is when his biographers - or editors like even Mitchell's - follow suit.)
(Not to mention that Fritz writing to Heinrich, of all the people, how anyone could have a grudge against poor him is hilarious for other reasons.)