This question has been tickling my curiosity for a while, and, if I were to make a guess as a male fan, I'd say Starscream and Bumblebee, two famous bots in general, must be rather popular among the female side of the fandom. I've come upon many female fans and creators who seemed to love Starscream, especially his Animated and Prime interpretations, and I recall a girl in high school who was really into the Bay movies and, when I asked her which Transformers was her favorite, she said Bumblebee like her heart was melting. I imagine Bumblebee is just cute to boot while Starscream is a compelling schemer and underdog - as well as fujoshi material with Megs for a niche of the fandom. But that's just my impression. I find those demographic questions pretty interesting, so I'm eager to hear from everyone!
Any good-looking one! Haha! As a young teenage girl (it's what we do) I had a huge crush on Prowl, Ironhide(movie) and Starscream. (Okay so maybe I am a little weird) Anyway, their still some of my favorite characters. Add to that Skywarp, Thundercracker, Jetfire, Hotshot, Sideswipe and Sunstreaker, Onslaught, Astrotrain and I'll stop now...
Starscream is the one who I think is most popular amongst girls, and it definitely has to do with all his different. you have bootlicking simp g1 Starscream, anime femboi/shark furry BW2 Starscream (probably no one cares about this verison tbh), edgelord/emo armada Starscream, chad prime Starscream, sigma grindset RID Starscream, and bad boy cyberverse Starscream.
Bumblebee was my first fav, later Jazz ... but very quickly I became a fan of Starscream (plus Slywarp, Thundercracker, Sunstorm, Acid Storm and all the other Seekers). Soundwave has grown extremely dear to my heart over the past few years (as have Rumble, Frenzy and Ravage). Then there are the Decepticon ladies Slipstream, G1 Flamewar, Thunderblast ... From the Autobots it's Prowl, IDW Perceptor, G1 Arcee, G1 Moonracer, Mirage, IDW Fortress Maximus, Windblade ... I better stop now because otherwise the list will be a little longer than I intended.
I’ve been aware of a large female fan base for Starscream well before the marvel films made Loki so popular
Yes, The trope of the elegant, smooth talking, not physically but still intimidating villain has been a trope for ever and has always been a fan favorite among women.
Since the 80s, my top 3 have always been Soundwave, Starscream, Shockwave. And Optimus, of course. For some reason, most of the other autobots never really appealed to me as a kid.
Speaking for myself, here's my top 10 each: Decepticons: Starscream Skywarp Thundercracker Octane Thunderhoof Night bird Soundwave Barricade Glowstrike Astrotrain Autobots: Optimus Prime Sideswipe Sunstreaker Jazz Ratchet Grimlock Wheeljack Windblade Arcee Bulkhead So I'd say a lot of my faves, are fan-faves in general.