I think it will be Alex Wesker.
Alex has been referred to by different pronouns in Japanese, making their gender ambiguous. We know they used Spencer's funds to do their own research on an isolated island. Revelations 2 will take place on an isolated island....
We can't possibly know what kind of research Alex was carrying. They reported to Spencer they were working on a immortality formula, but Spencer was a finished old man, and would be easily fooled.
Since people are keen to see the mysterious woman as being someone’s mother, then why must she be Moira Burton’s mother, or Sherry’s mother?
Annette Birkin is not a character that only the hardcode fans would be able to guess. Even minor fans could tell you who she is if they’ve played the hugely popular RE2.
Unless this Alex Wesker really is a female (Alexandra) and is the actual mother of the Ashford twins, Alexia and Alfred. Their father was called Alexander remember. All names correspond. This would be a ridiculous twist, but it’s not absurd for resident evil. The guys at Capcom are more than prepared to change something for the sake of a new plot. If you know them, you wouldn’t put it passed them. British aristocratic toffs are completely ridiculous anyway. What happened to their mother again? I forget. Lord Spencer and his Wesker children project, is not too far in the left field regarding the Ashford family. Let’s say their mother has superior IQ and were selected and became one of the Wesker children.
Now what would be the connection between her and Claire or Moira?
Claire (instrumentally her brother) eliminated Alexia in Code Veronica X. She was blown to smithereens with a rocket launcher! Perhaps in the twisted Ashford mind, the Redfield’s are countable for the destruction of the family, the palace, and the island.
The circumstance of Revelations 2 is definitely reminiscent to Code Veronica with the Island prison surroundings. It might be a hint at something. I take Moira as a young sidekick, relating to the fact that Claire has always taken the mother figure role. (You could argue that she even had to babysit Steve!) And as Moira is Barry’s daughter, it is like bringing a part of him back.
The idea of Barry’s wife or (other daughter) being evil is just silly, desperate even. I don’t believe Capcom have gone that far down hill yet.
There is more correlation with the Ashford family and the familiar surroundings that which Code Veronica and Revelations 2 share.
The Annette scenario would be a predictable and ****ty revenge plot. Come on! And If I remember correctly, she was fatally clawed by her mutated husband in the shaft in the underground laboratory. Shortly after, the entire place detonated. I know, I know, Ada survived remarkable odds. But I’m optimistic the game series has moved on - it is a bit more sensible these days.