Without going into too much detail as I'm using a mobile device, the 2 games I include into the established "official" timeline are CV64/ LOD.
I like to believe that either Dracula did inherit his wolf form from Cornell or that he inherited the full Lycan form as seen in LOD's ending.
Since Dracula the novel is canon, the latter especially would explain the killings in London (inferred to be the Ripper murders) and why the novel describes a beast who committed them.
If the former is true then one would have to explain why Alucard also has a wolf form.
Regarding CV COD, I believe St Germain is Eneomaos since he'd mastered time he was the one who left Hector all the hints under an alias in order to assist his success.
Legends and Resurrection happen in their own separate timeline.
Cotm is not linked to any other game since the setting is Austria.
Mathias sought/ used black magic with those who dabbled in it described in the Dracula novel to acquire the Crimson Stone.
My assumption is this was done by making a pact with Satan, which started the manifestation of Chaos by Mathias denouncing God. As part of the pact a sacrifice was required, by which Mathias sacrificed his own humanity, eventually becoming Lord of the Vampires.