I didn't like the Transformium concept in AOE, but I could appreciate it for what it provided: a nanotechnology Transformer that could form itself into a fluid shape. Still, nanotech is better off used as a tool instead of as an alternate mode. - Man of Steel had alien liquid nanotech being used to form shapes and weapons - the GI Joe films had Cobra Commander develop nanotech for soldiers to use to improve their strength, give them face-disguising qualities (and mind-control) - the Sentinels in the Days of Future Past film had nanotech designs, forming their bodies into shapes So which Transformers do you think should utilize nanotech? The Insecticons, or any insect-like Transformer for that matter, are the most likely choice, since they're able to form hive minds and they've got that swarm concept that would be appropriate for nanotech. Bombshell would be perfect with his thing for cerebro-shells, Shrapnel would use it for breaking up his body, Waspinator would be blown up repeatedly, etc. They'd be the most fitting choice.