I want to try to give her a dial with at least the mystical Keyword. whats your ideas?

N'astirh. Got flight, got mind control, got steal energy. That was my first Mystical KW fig that came to mind

That is a good choice and was 1 I thought of but I was trying to see if there a modern age figure that could work cause I like to play her and we pretty much play modern at my venue.

Modern Age, the Mystical Keyword, has Flight, has Psychic Blast:

Circe from Arkham Asylum is great. Her disdain for men, being a female character, and all fits Morrigan quite well.

Failing that, the Adam Warlock Common from GG works great, as well...RS/PB and Perplex. I'm not sure about the damage reducers and ego-swapping, though.