If it’s enough content, an AI can learn any language naturally just by training on it.

Only solution is an encrypted airgapped computer that cannot physically connect to anything. But the set up makes you suspicious enough to get in trouble just for having it probably.

There was an encryption software a while back that would open two different partitions depending on the password you put in so if someone forces you to open it under duress, they get the drive filled with naked ladyboys instead of the one with your revolution plans.