You guys might be interested in this
old thread where SH's armor and Shar's iconography came up.
That was a very enlightening thread, thank you. To sum it up, though, everyone is basically confused as we are, lol. Grey Ghost has a fantastic experience I'm willing to except, but it does kind of go against the way Sharrans typically act. They love working in the dark and being deceptive, so they really would be the kind to proudly show off their religion unless they needed to. Even for a blackhat mission, I would have imagined they would have been careful anyway out of habit and practice. I mean, the Gith are fairly powerful and even if they're killed the last thing you want is to make it obvious it was Sharrans who were having a go at you. That gives them threads to follow.
I struggle to imagine Larian doesn't realize this as Shar is portrayed a ton in a wide range of content and is typically pretty consistent, and even more stuff has happened since the many bygone editions that put Shar in even less of a good light (haha). Maybe this just leads credence to the suspicion that she's someone else's brainwashed or tricked priest, likely Selune's. That would go right in line with one of Shar's major domain aspects and them generally being devious, and I can imagine slapping Shar armor on her would only help sell it home.
The way it's written though is still pretty weird characters remark as if there's something odd about her when her armor just gives it all away, lol. I'd probably count on it being changed for release, to be honest.