For those who are interested, my friends and I have a book club that intersects with a lot of these kinds of topics. It's called Public Works because it’s dedicated to reading books in the public domain. We're in the middle of reading Thucydides right now, and it’s part of a larger arc on classical antiquity. All are welcome. Meeting information is on the website (https://r33d.org) which is updated at the end of every week. Hope to see more HN'ers there!
If you are interested in physical copies, I highly recommend "The Landmark Thucydides: A Comprehensive Guide to the Peloponnesian War" , and others in the Landmark series. I got a lot more out of it with all the maps and explanations. Very well done.
The translator Steven Lattimore is still alive. GP probably won't live to see the translation become public domain. As an alternative: read the J. M. Dent translation and then, if you want to study it from first principles, learn Ancient Greek for the real thing.[1]
That's right, Lattimore is not public domain. It's ok though, our focus is on the original work, and if it's in another language we just pick the best one that suits our needs. Other people in the club have stuck to Crowley though, and I'm going to check out Dent (per the sibling comment) when I have time.
If you're interested in lectures I can recommend The Peloponnesian War by Kenneth Harl published by The Great Courses (also available on Audible). It's one of the best lecture series I've listened to in any subject.