Those are basically the ones i was thinking of, but theres a one-off mutant named "Miranda" that shows up in the Worst Xman Ever miniseries.
Her power is complete control of marvel continuity. She's the reason Tony Stark is still in his 30s despite being created around the time of the korean war, shes the one that keeps the original 5 xmen around since the 60s with a sliding timeline, she's the one that brought Bucky back as Winter Soldier, shes the one that replaced Nick Fury with a better one that looks like Samuel L Jackson. Shes not from 616 but is obviously aware of the multiverse and roams around in "idea space" when it suits her.
She's saved the world hundreds of times over by rewriting marvel continuity, and has been doing it in real time since 1960.