There doesn’t seem to be any rule here against being a member of an anti-freeper site. That alone will not get you banned, as far as I know. But it is a reflection on you. If you join an anti-freeper site, knowing it’s an anti-freeper site, it makes little difference if you joined because it’s anti-freeper, or because you’re willing to tolerate and participate in it’s anti-freeper nature just to be among your friends who despise everything we stand for. Like I said, that won’t get you banned, but you won’t be very well liked or respected here.
I don’t think WA is an anti-Freeper site. And there is certainly nothing WRONG with being a member of both sites, and any number of other sites for that matter.
As to whether having an account at WideAwakes is a “burning at the stake” offense on FR, I would hope not.