I like Sonia.
But her storyline should be kept separate from the IGA-Canon (which is basically the official Canon), like Nathan Graves, Desmond Belmont, and Reinhardt Schneider.
An even better example, would be Gabriel Belmont and his entire set of games. They're their own encapsulated universe and timeline.
Think of it as the different incarnations of the X-Men comics, where a remake or retcon, etc. change who and what is being done and when.
In an Universe, Sonia was the one to come after Dracula, armed with the Whip and knowledge passed down from her family.
In yet another Universe, Gabriel Belmont in the 1000's was part of the Brotherhood of Light.
And yet, in another, the normal canonical events, starting with Leon and Rinaldo, happened with slight deviations, resulting in stuff like, for example, the potential loss of Belmonts in the 1800's, cueing EITHER Shanoa's Game, OR Cornell/Reinhardt/Carrie's games. This one universe is even further twisted by the TimeTraveling demon Galamoth, and his cohort TimeReaper. The 64 games aren't technically canon but if Cornell made it into Judgment, which is an IGA title, then this can be explained due to the events in that game.
Time Travel, Aeon, Galamoth, TimeReaper, and St.Germaine are the potential reasons for a convoluted timeline in ONE universe, which is the Canon Universe.