Bumblebee-Strafe, Optimus-Grimlock, Megatron and Starscream, and Soundwave-Laserbeak. I really like the idea of the Dinobots as the Autobot cavalry, and I rather like that Optimus has to beat some sense into Grimlock to get the Dinobots to charge into battle. Optimus and Megatron for their banter and dynamic in RotF and DotM. Soundwave and Laserbeak for both being allies of Dylan Gould and for Laserbeak happily murdering human collaborators for his masters! I also really like Drift and Crosshairs when they're together. Those two get in fights or confrontations with many other Autobots (Bee, Hound, Mini-Dinobots, Daytrader, Cogman) but not each other. I find that interesting given Drift and Crosshairs are very different characters from each other in some ways.
Shouldn't the Twins and Wheelie & Brains be an option? Yeah, those two have a great dynamic. I personally love all the Megatron Starscream scenes in the films so I'm going with those two. 2nd place Wheelie & Brains, 3rd place Drift & Crosshairs.
I meant to add Wheelie and Brains so I might do a Part 2 To this With Wheelie and Brains Skids and Mudflap Drift and Crosshairs Nitro Zues and Mohawk Optimus Prime and Dragonstorm Drift and slug Crosshairs and scorn Ironhide and Sideswipe
Sam and Mikaela, because none of the Transformers get enough screentime to deserve names. But in reality, I always liked Barricade and Frenzy. I've always wished that there could be a cool stealth-like level in a video game featuring Frenzy, then you have to do the getaway chase as Barricade. That would be so cool.
Ironhide and Ratchet seemed to have a nice buddy dynamic going, if only a little bit, especially as they're basically Optimus' right and left hands not counting Jazz. Crosshairs and Drift are cool too. As said they're such opposites but they've never argued or anything. They make a cool team, with Drift slicing and dicing, and Crosshairs peppering the enemy with blasters. It's also funny how Drift may seem like the calm one compared to Crosshairs, but really Crosshairs is the more stable one as he's not flipping out at baby Pteranodons ready for the kill. Definitely a fun duo. Yeah they're totally banging.
Drift and Crosshairs. I always liked their designs and how although they are completely opposite personalities they work together well and get along better than most Autobots.
I don't know if most of those qualify as bonefide duos, do they? Just because they shared a second of screen time together? I guess Drift and Crosshairs are good for the reasons @Chopperface mentioned, but I see them more of a 3some with Hound tbh. Megatron and Starscream offered a few of the few stella moments surrounded by the shitefest that was ROTF, but even that kinda failed because they only captured Starscreams pitiful side, and forget about his conniving elitist side. I was looking forward to this Bee and Rodders brothers in arms stuff, but that turned out to be a non event, thanks TLK. Ironhide and Sideswipe made a good team, but only for a scene. I could definitely stomach a spin off of those two, but I guess it's too late to can Bumblingbee the movie. Hmm, I dunno, they still have a lot of work to do with the MV before we get our Thor and Hulk! I do too, the only thorn is Optimus' line to Grimlock.