So many, since I mostly write #historicalFiction and riff off the historical or archaeological record to flesh out into stories. What if Princess Neferure of the 18th Dynasty of Egypt suddenly disappeared from the historical record because she got her gay happily-ever-after? What if an ancient Chinese war sparked off by a dispute over trees had a star-crossed queer love story at its heart?
This is fairly standard for the genre, but there are events I'm taking "out of period" into a much more ancient era, like the 13th-century defense of Chungju Fortress from the Mongol army. The commander, charged with defending the fortress with a force of soldiers and enslaved people who had already suffered much from the war, freed the enslaved and promised all of them official titles. There's no record of any of that happening in 1st century BCE (where records themselves are fairly scant), but I'm taking inspiration from that for use in my own big WIP.