Yes some people may have the type of alters who's job, purpose reason for being is to not talk, not move and not interact but they still have a mood, behavior, affect....basically everything that makes them an alter. example an alter of this kind may have a neutral mood, angry mood, may clutch their fists, maybe they suck their thumb, maybe they squeeze their eyes shut, maybe they pinch their mouth shut... an alter with DID has human traites/characteristics that distinguish them from the host and each other.

with epileptic seizures the body twitches/convulses/ loss of bladder control (most not always), pupils dilating, sometimes the person looks like they passed out after the seizure, sometimes the person looks like they are just staring and sitting still while their body is having a petit mal epileptic seizure, and other physical changes in the body and brain. non epileptic seizures mimic/presents itself like a copy of epileptic seizures.

I bet if you went to youtube there might be some vidoes of what a pseudo seizure/conversion disorder seizure/epileptic seizure looks like and what a person looks like when they are switching into and out of their alters.