@mjangelvortex
The Insecticons were the first instance of Cybertronains that consumed organic (and inorganic) matter for energy in the cartoon explained as a survival modification by their escape pod.
This is used to explain later developments in Maximals and Predacons being able to eat.
Pretenders (which also are considered tied to Maxies and Preds to as an evolution on organic looking disguises) also are capable of fueling buy eating.
IDW introduced the process
pink alchemy in which organic life forms are broken down to create Energon Cubes Ask Vector Prime would retcon that the Insecticons way of eating as being a form of this process just internalized.
Powermasters were explained as a way of organic fueling in which an organic being essential becomes the cybertronain’s “stomach”.