Even in the game, it is clear, Shadowheart makes it clear herself, people don't like Sharrans. She's nervous you'll immediately boot her from the party because she's a Sharran. It's made totally clear, if you trigger the right dialogues and pick up the right books that Shar is a well known bad goddess.
And the mural. That's the biggest indicator. You don't need a roll when you look at the mural. The game just tells you, "The bad guys in the mural have the symbol of Shar.".
So you recognize it there, but for some reason, nowhere else.
You do need a roll when you look at the mural. I've had characters fail at figuring out what the mural represents.
Anyway. You're making an argument here for how Shadowheart herself doesn't expect anyone to be able to figure out who she worships by way of her decorations. If she did expect as much, she wouldn't be outfitted that way.
Originally Posted by colinl8
If the players who know the lore are bewildered by her appearance and how people react to it, her appearance and/or other characters' reactions should change
I disagree. The sample size of "players who know the lore and etc..." isn't large. There's a handful of people here, at best. The whole topic was pretty much an echo chamber before it was challenged.
And I argue that it was an echo chamber because someone pointed out the black circles all over Shadowheart's design and made a joke about how obvious her secret is. And others agreed, not thinking through whether or not it was actually obvious outside of hindsight. Then people got committed to the notion as they became invested it, sometimes making the same joke themselves. And once committed to it, pride kicked in. It became a matter of identity. "I know so darn much about Forgotten Realms, I can't be wrong. Only evil people wear onyx in DnD!"