Supernormal Step/WMG

Hall was beheaded at one point.
Given the scar that encircles his neck, this seems fairly obvious, and it's a common theory among Supernormal fans. Still, it's not confirmed. If this is the case, though, it speaks volumes about the extent of Hall and Eva's Immortality.

Akela is a lesbian/bi.
Not extremely obvious, but seems to be hinted at in the way she reacts to people, and body language, especially in panel one of this page.
 * Right on the money, sir/madam. All but confirmed here and here.
 * And confirmed!

Fiona's father knew that fiona would travel to the other verse
And so, he trained her like Sarah Connor did with her son...
 * Unlikely when you take the rest of the story into account. Given that the way she got there has been revealed and was completely unpredictable, plus the fact that half of what her father taught her is inapplicable given the differences between universes, it seems unlikely that he had any foreknowledge regarding her fate.

Elvina and Britta are clones of Inga Jorgenson.
Given that Hall and Eva are evidently clones and that Inga was the project leader with a Strong Family Resemblance to our favorite bumbling twins, it seems likely that she was cloned as well.