here's a fun one: AU where in the G1 movie, Bumblebee is taking care of Daniel while Hot Rod is on Moon Base 2 -I'd like to think it ends with Bumblebee becoming Goldbug Prime, with a VW Bus altmode.
Basically Bee arrives in the middle of the iconic Optimus-Megatron standoff and wastes no time in taking a position at Prime's side. During the standoff, Megatron attempts to capture Bee and hold him hostage, but Bee wrestles free of Megatron's grip, flips over Megs, and shoots him in the back. However, while Optimus runs over to Bee to check on him, Megatron takes careful aim and gets him in the side, causing him to be knocked back and fatally wounded. Bumblebee carries Optimus back to base, and the Decepticons retrieve Megatron in kind as they retreat. -The rest of the movie goes mostly the same, with Bumblebee reassembling Kup and maybe even bringing his own Energon goodies? They still get locked up, but Bumblebee thinks of a plan. He suggests that they use 'that one maneuver you perfected' to escape from the Sharkticon pit. They eventually regroup with the Dinobots, and Bumblebee befriends Wheelie. Ultra Magnus struggles with the Matrix, but Bee does his best to reassure him. When they get to Junk, the Junkions are hostile until they see Bumblebee and start quoting Herbie and various bee-themed product promotions at him. The crew asks about Unicron, and the Junkions actually join them out of respect for Bumblebee.
When Bumblebee is separated from the rest of the crew, he finds Galvatron in the depths of Unicron and fights him for the Matrix, but Galvatron overpowers Bumblebee and damages him heavily. As Galvatron leans in close to gloat, but while he is leaning in, practically eye level with Bumblebee, Bumblebee grabs hold of the Matrix...and his optics fade out. Triumphant, Galvatron attempts to take the Matrix back from Bee, but as he does, he is repulsed by a shining, golden light. The Matrix repairs Bumblebee as Galvatron watches in fear, recognizing what is happening. He fires a few shots, but they all are reflected, ricocheting into the walls as Bumblebee, now in a new body, stands tall with the Matrix over his head. Optimus Prime, speaking from within the Matrix, says 'well, old friend, what shall we call you now?', to which Bumblebee responds 'well, given my new body, I think Goldbug Prime would be appropriate.' The newly-christened Prime uses his newer, more powerful stinger pistols to knock Galvatron into the depths of Unicron before running to find a new exit. He regroups with the other Autobots and transforms into his new alternate form, a stylized take on the VW Type 2 Transporter, while remarking that 'it feels right. Nostalgic, but different' as the other Autobots transform alongside him and exit Unicron, right before Unicron explodes. Galvatron is flung into space, screaming about the unfairness of it all.
