No they are not the same group. The Sisterhood is a group of women I created a long time ago due to all the heroes in the playing group seemingly to all have the complication, disadvantage at the time, "Won't fight / harm a women". I figured a all women group would be a interesting concept.
On another note, I was talking with Jason and he has given me permission to write-up WITCH. I'm torn in what direction to take the group, I haven't decided if I'm sticking to the terrorist theme or more of a supernatural theme. This is what I have found out about the group, all is from the background of the villain Gremlin.
Linda Shane was not the prettiest girl in high school,
and a number of bad experiences with men drove her into the arms
of a radical female terrorist group called WITCH.
The WITCH organization is a loose alliance of a few radicals.
They believe that it is morally just for violence to be used against the
enemies of the woman's movement, be it bombing video stores that
stock pornography, terrorizing prominent politicians that are seen
as anti-woman's movement, etc. Legitimate women's groups
unanimously condemn WITCH, but WITCH doesn't care. WITCH
doesn't employ magic; the name represents what its members
believes is the pinacle of radical feminism; witches are persecuted
(as they believe they are), and are powerful enough to need no one
but themselves (WITCH condemns anyone who doesn't agree with
everything they believe).