Some other things revealed at Robocon's virtual event, and the BotCon people from earlier this year (which I only recently came across).

The panel to talk about next year's BotCon. (I haven't watched it yet)

A reveal from the Transformers archive, about a proposed version of the original Universe line back when Armada was on. It was called Transformers Super Cross, and it's description suggests that it might have been multi-verse type of toy and cartoon series to follow on from Armada, but ended up being split up into Energon and Universe instead. The link has some images of the story outline, which has Aaron Archer's name on it.

Back in 2002, with work on Transformers Armada wrapping up and Energon yet to be drafted, the design team were contemplating the next escalation in storytelling after the defeat of Unicron. In a massive 4 season, 52-episode saga called “Super Cross” (or “Super-X” for short), Cybertronians would discover that their victory over the evil god of chaos was not as final as they had thought. And they would need the help of the All-Sparks – important Autobots, Decepticons, Maximals, and Predacons from across the Multiverse, to come together for one last stand. The outcome after this crisis? A single joint timeline with everyone’s favorite characters in one place and time!
Unused BotCon sample of "Unicron Trilogy Ratchet" from the mould that they used for the 2014 Cannonball toy... but since they had so many QC problems with the Cannonball toy, they decided against using it again.

I think I posted this somewhere else, but in case I didn't, another unused BotCon concept was this Shattered Glass Optimus Primal done in Beast Wars Megatron colours and a mini Onyx Primal.

And maybe you remember a couple years ago when we revealed that one of the potential/canceled exclusives was Titans Return Onyx Primal. But that wasn’t the only time that an homage had been planned!

When word came down that the license was ending, we wanted to make the final TFSS subscription “freebie” figure an homage to something unmistakably “Club/BotCon”. The Hasbro-approved final freebie at the time was Combiner Wars Sunstorm. We wanted to switch it out though. And the figure we wanted was… Shattered Glass Beast Wars Optimus Primal! This would have been a recolor of the Pretender Optimus Prime in SG colors with the Micro/Targetmaster in an Onyx Primal scheme!
(in case the concept images in the first post of this topic on facebook disappear, they are also here as well)