#firecons

Well, I wouldn’t say his time with the Decepticons was ALL bad. In fact, while staying with the Autobots, some familiar faces may turn up at the Autobot base now that Starscream is hanging out there!

For a lot of people, the war has essentially been over for nearly three years (due to both Optimus and Megatron being out of the picture). Now that Megatron is back, not everyone wants to go back to war, and some of the Decepticons that had been hiding out on Earth are starting to reach out for help. I think with Starscream staying with the Autobots, he'd become a sort of liaison between ex-Decepticons and Autobots. This isnt to say they're all living at Autobot base now, some of them might, while others like Swindle are out doing their own thing and only showing up to trade or whatever else.

Because Obviously they exist, Trion turns into a robotic lion and Onyx's presence implies there's more of them, question is where are they?

I would suspect the reason they are not present in the film is because either Sentinel and the Quintessons drove them to near extinction or perhaps Sentinel sold them to the Quintessons as slaves (which could explain where the Sharkticons come from)

Or perhaps instead in an extension of Sentinel's caste system (and taking a cue from idw), the beast formers are the lowest of the low, treated literally like animals and forced out of society

How did Gnaw and Cindersaur become members of the Predacons and Terrorcons, respectively?

Dear Legends Leftover,

In the case of the former, it was more by accident than anything. Gnaw had been the leader of a team of Sharkticons sent into the depths of Cybertron to pull the large switch controlling the Exponential Null Generator. When that plan went awry, he ended up following Galvatron to the surface, and from there to Chaar, without being noticed.

When Galvatron finally stumbled across Gnaw (chewing on the base of his makeshift throne), the Decepticon leader threw him to the Predacons—declaring that since they were both spawn of the Quintessons, they should get along fine.

Razorclaw knew better than to argue with Galvatron when he was in one of his moods, and reluctantly accepted the Sharkticon. When the Predacons went on their hunts, they would toss the scraps to Gnaw, keeping him around as a living waste disposal machine.

Cindersaur, by contrast, was deliberately headhunted. Hun-Gurr had been keeping his watchful eyes on the Combiner Wars, and had seen the other combiner teams picking up new members to replace fallen ones or to increase their number. The Terrorcons' rivals, the Technobots, had acquired two new members even, which stirred envy in the Terrorcon leader. Still, Hun-Gurr was not about to recruit just anyone to join his squad; he wanted an outcast—someone whose loyalty would lie with him over any other Decepticon. He found the perfect bot with Cindersaur. The Firecons had recently broken up, and Cindersaur had found themself lost without their teammates... literally. They had gone on a rampage, ending up completely disoriented in Chaar’s wilderness. Their usual means of retracing their steps, by blazing a trail behind them, had completely failed them in a landscape where everything was already burned and blackened, and they'd been wandering in circles for months.

Dear Canny Cryptozoologist,

It just so happens that the Ancient Decepticons of Earth, who took the guise of legendary "monsters" on your world, included a number who'd taken the form of what you call cryptids. Such examples include Diabla, who inspired the legend of the jersey devil, Heavytread, Abominus, and Stinkbomb, a trio that posed as the sasquatch, yeti, and skunk ape respectively, Botanica, who menaced the Flatwoods area, and Wingthing, who became feared as an omen of disaster in the west of Virginia.