Sorry if this rambles a bit.
I've been pondering Battle Ground and Peace Talks.
When Molly launches into the explanation of why she can't step outside the circle in PT, it's also a clue for later on. Her mantle is more invasive than Harry's. Shedding her mantle the wrong way would damage her. And Harry's can inflict pain if he goes against Mab's word. Which probably means that Molly can't go against Mab's word. But as we see in The Good People, she can do as she pleases provided she doesn't.
She has some free will, but nowhere near what she had as a mortal. But, there's no way Uriel would stand for a total loss of free will or the loss of an immortal soul. So, we can assume that she's still mortal, but under a geas and a glamor. Jim has said that the mantle is changing the bearer's DNA, but that could be explained by Molly and Sarissa looking like twins now.
So, she's got to behave as a fae would, equalizing scales, hoarding knowledge, vulnerable to iron.
She also appears more fae when she's leaning into the mantle, like when she was coordinating communication for the fae and addressed Harry as Mab would, with eyes and ears totally fae. Was that because her mortal mind was occupied and left the mantle to answer Harry? Because, coming from a tripartite entity like Hecate, you have to assume three or all six queens have some sort of hive mind, at some level.
The final point I want to bring up is during the limo ride to the Carpenter's house, Molly leans into Harry's hand and tells him, "You're my knight too, Harry." I don't think that was the Winter Lady speaking. She made sure that they were isolated with no outside observers. And the Winter Lady has never given the knight an order. In fact, everything we've seen about Winter Law argues against it. Winter Law is whatever Mab says it is. Never Molly, Maeve or even Mother.