Oh, goodness I wonder how Solas would have reacted if he knew Morrigan was Mythal's daughters.
I wonder if Morrigan views the Crossroads like any other human.
I wonder if it ever bothered the Mythal part of Flemeth that all her children could be was human.
I wonder why all Flemeth's children were daughters.
I wonder if being Flemythal's daughter changed Morrigan in biological ways (ie not just how she grew up, what she learned)
...
^.^ So many questions!
My theory/headcanon is that Morrigan and Flemeth's other children aren't daughters at all, but rather pieces of Flemeth. Flemeth has raised these fragment, her daughters, for centuries. Some are aware of what they are, others like Morrigan, are not. But they are all Flemeth. A bit like the fragment of Flemeth that is created if Hawke takes the necklace to Sundermont and the HoF didn't kill Flemeth. There are two Flemeths then. One is absorbed, we assume, the other keeps on trolling Thedas.
Back in DA:O Morrigan was partly right. All Flemeth's daughters are all Flemeth--Just not in the way Morrigan believes.
So, when Flemeth tells Morrigan..."A soul is not forced on the unwilling." She is telling the truth--or at least only lying by omission. You can't force your soul on yourself, after all.
Another random guess... at least one that keeps me from despising Mythal outright. It's possible that she picked Flemeth, rather than an elf, is because Flemeth was disposable. Okay, that's not much better.
But rather than endanger one of her people--she possessed a human. Of course, that doesn't explain why she chose to squat in the woods for a few centuries, while people suffered. She sure didn't mind using them when it suited her purposes (Sundermont)
But then, I have a feeling that Mythal was no where as nice of Solas has led himself to believe. She did, after all, own a well that enslaved people all the way into the afterlife. That just doesn't scream, "benevolent leader" to me.