Accents

In virtually all versions of Transformers fiction that involves audible voice work, the voices of those Cybertronian characters feature identifiable accents. While the vast majority speak with what could be described as a generic American accent, there are a plethora of examples across different continuities of characters who speak with strong accents that are similar or identical to other human accents.

The "behind-the-scenes" reason for this is reasonably simple — in a show where thirty different robot characters have speaking lines, a memorable accent or vocal quirk helps distinguish between "the red jet guy", "the blue jet guy", and "the white jet guy". Furthermore, for better or worse, these stereotypical presentations help give audiences a "mental image" of the character — the guy who talks like a beatnik is probably laid-back, relaxed, and totally cool. The guy with the slow drawl is a rough and tumble cowboy who doesn't particularly cotton to all that fancy business, pardner. Accents, in this context, provide a sort of "cultural shorthand," which is not even limited to Western audiences — Japanese audiences have their own cliched stereotypes as well.

There's also the voice actor angle to consider — some actors play multiple characters within the same series, and adding various accents helps distinguish between them. Having two characters who sound essentially similar, save that one is "Australian" and one is "American" allows a VA to play multiple roles discreetly.

The in-story explanation for all of this is usually... lacking. Most continuities do not explicitly point out how or when the Transformers learned to speak the dominant native language upon coming to Earth, and indeed will often have scenes — particularly flashbacks - which depict them speaking Earthly languages with their individual accents while still on Cybertron, before encountering humans. If one takes these scenes somewhat literally, it would indicate that these accents or some kind of approximations (although probably not the language itself) are somehow native to Cybertron — after all, lots of planets have a "north". Although it could be speculated that different Cybertronian social groups, class structures, geographical regionalisation or even ethnicities may be the origin of these differences in accent, it is an issue which remains unaddressed in official fiction.