Canonically only one character is gay, Widomaker is asexual, obviously the robots don't have actual genders. As for the Mercy/Reaper theory, I thought in the Canon Blizzard has set up, Mercy did make Reaper by accident with her attempt to revive him.
I thought Blizzard said that atleast one character was gay? That’s what I remember hearing, but I’ve seen others say that two are, or just one. So I dunno about that. And Widowmaker isn’t necessarily Asexual. Aromantic KINDA makes more sense for her, but that’s because she was brain washed by Talon, not her choice, so I don’t know if that would exactly define her orientation. Cause she was with Gerard as Amelie after all. And I dunno if it’s exactly confirmed, but for the Mercy/Reaper thing, I dunno, I’ve seen two separate ideas mainly, A. Mercy tried saving Reaper, causing his problems or B. The explosion in the Switzerland caused some of Mercy’s research or technology to backfire. If you can correct me on anything, definitely let me know! -Knight