>>56269171It can impersonate for a short while but not too long. Speech (non telepathic) is actually a move humans use. That's what enables us to command pokemon while they can't (oranguru is probably our closest ancestor). The pp (power points) for speech is incredibly high (even more than constrict) and so we can usually talk for a while without resting. However since Dittos transformation ability has a max pp of 5 on all moves, it won't be able to handle more than a few sentences before becoming mute. If you suspect someone is a ditto, try to have a conversation with them. If they've been discovered, they shouldn't pose too much of a threat since they only have most of the stats of a human, however if they're high level then you might need a bunch of people to gang up on them to chip at their unchanged Hp stat.
