I've seen so many posts lately about how Grace wouldn't add swears to their translator but I 100% think he did.
He's not morally against swearing, he said holy fucking shit when he saw the Blip-A for the first time, the only reason he doesn't swear normally is because he trained himself out of it because he teaches middle schoolers. If I'm remembering right, he even calls one of the kids a smartass in his internal narration at one point. He's spent so long not swearing that he's not just going to fall out of the habit immediately.
We know that at some point, he learned Eridian swearing anyway because Rocky swears in the final chapter of the book. And I think he learned most of them when Rocky reamed him out after leaving the taumoeba collector out at room temp.
Plus, Rocky is an adult and Grace treats him like one, which includes adding swear words into their translator so that Rocky can express himself.
