Rodimus Knight wrote:It would make some sense to use them since they already have the models worked up in the computer systems. I would assume that would save them a lot of money right there.
Most of those designs would need to be heavily altered or changed entirely, take a closer look at the designs from Bumblebee, the only ones that look like they could transform to any type of convincing Earth vehicle with small edits are the ones that were designed as Earth-like vehicles first before the Cybertron sequence was even conceived which would be Optimus, Bumblebee, Shatter, Dropkick, Starscream/Blitzwing/Seekers.
The rest of the designs were "kitbashed" using these already existing models such as Shatter into Arcee, Bumblebee into Brawn or Optimus into Shockwave/Soundwave and quickly made in a few weeks, their not polished designs for main character roles. (Brawn, Shockwave and Soundwave are the worst in this regard, there's almost nothing about them that looks like they could transform, almost to the level of AOE Galvatron who had the point that they didn't transform traditionally anyways.)
The Earth mode versions would need to be almost entirely new designs bar things like head/hands/feet presuming they were not integrated with any vehicle parts, so the existing assets excuse only helps to a pretty minor extent.