No, Tanezaki Atsumi is god-tier (Juju in Sono Bisque, Chise in Mahou Tsukai no Yome, Vivy in...Vivy, Emporio in Jojo, Emilia in DRRR, the triplet Chiis in Centaur no Nayami). She plays children extremely well, and Anya is her best work on that aspect yet. On top of that, I'm not sure how the dub you're watching works, but Anya speaks in a very childish dialect of Japanese, that even someone not fluent in the language picks up on immediately. Mixed into that are random words that someone Anya's age should never be using (linking to her esper nature), and some specific references to classic series on rare occasions. Tanezaki Atsumi is the closest I've ever heard to actual child actress casting.
Anya has not had a particularly sheltered childhood to date. She's seen some shit. She's heard way too much from inside people's heads. As for seeing someone actually murdered in front of her? The 'unreality' of that kind of situation puts strange dampers on it when the psyche protects itself. Again, not sure about the German dub, but Anya's line isn't delivered like that at all. She's very troubled about reading "a real bad guy" in contrast to her cartoons.However, one thing I feared became true: The very realistic violence completely goes against the otherwise lighthearted nature of the show. In episode 1, that gangster boss casually shoots an underling in the head - to which Anya makes a funny grimace and think "that is a bad guy". :/ A child just saw someone get murdered, she should be terrified, crying, and not make funny remarks.
Yor is an assassin, and what she does is kill people for work. She gets told who to kill, and she does exactly that. The end.And now in episode, Yor. Her entire character is bad, because when it comes down to it, she's a murderer. And don't give me "she only kills bad guys", the episode itself said that she's part of countless "dubious" missions, so it's unlikely to be this clear cut. And maybe it's me getting older, but I don't mass murder "cute". When she slashed those guys in the hotel appartment dead, that just wasn't fun. And her being shocked over her dress being ripped also wasn't funny. Portraying deadly violence like this might work with braindead Americans, but for me it didn't work.
The "good" and "bad" should be viewed through the lens of who they work for. Twilight works for WISE, and Yor works for Garden. WISE is part of the government in Totally Not West Germany, and Garden is based in Totally Not East Germany, but Garden is not the equivalent of WISE. Garden isn't a spy agency. Yor kills people based on however they get their orders/requests/hunches/culling/whatever. Period. She has been told it is for bringing peace, and without knowing how those jobs come down or from who, that's what we know. Is it for Ostania? Is it for Westalis? Is it for a criminal organization? We don't know.
Being shocked about the dress isn't particularly humorous. It's meant to show how casually Yor murders people. She's more worried about the inconvenience of a tear in a dress she needs for a social function than how to clean up 20 bodies, or if there would be any threat to her leaving after she made the commotion and mess. She's overwhelmingly superior in all physical aspects to Twilight, or basically anyone else shown in the anime to date.
Yor's entire value system is kinda fucked up because she's been doing this work for so long, and now she's acting as Anya's stepmother. That is the joke. It's in context to Anya and combining three very problematic individuals into a family for a mission that is supposed to prevent a new war between the West and East.