So, the Japanese have about 50 different levels of politeness when adressing your boss/dad/grandmother/postman but they don't have any swearwords?! So what do they do when they stand on a lego brick or a plug? lol
Anyway, I guess that complicates things a little, so I guess Hito has got to make a judgement call? If it were me I'd toss in a few pisses shits bastards and fucks where appropriate.
Eg 'Cloud was surprised to find that the bastard shit fuck Don Corneo wasn't dead, and he was even more surprised to find the fucker had taken photos of him'
Seriously, I'd just have the swear level equivalent to a 15 rated film, nothing too gratuitous, just appropriate to the situation, mortal danger/anger and whatnot. Or if theres any doubt just leave ________ and we can fill in our own swears