All change have been made to make Jason more canon-wise. Thank's to ThePlotTwist who advised that i should make Jason not a Belmont wich i just realized making him the son of Julius Belmont pretty much contradicts everything in the canon classic verse! Instead of being a Belmont, Jason's a Schneider meaning he's a decendent of Reinhart Schneider and Schneider is pretty close to a Belmont if you ask me, maybe they are both cousin family?
And who knows? maybe Jason could be a Belmont in the LOS verse? i mean Victor Belmont in the LOS verse did not have an amnesia of his bloodline unlike Julius Belmont!
One thing I must make clear: You could STILL make your character related to a Belmont. My point was specifically because it's very, very hard to create a Belmont related to the other Belmonts without screwing up something on the canon. Whereas, making him unrelated to the Belmonts gives you a much bigger space for creativity to flourish.
Now, however, making Jason related to the Schneider (specifically being a descendant of Reinhardt) basically caused your character to be completelly removed from the canon. This means that it's impossible for Jason to even know who Soma is. And this is because Castlevania 64 is not canon to the universe where Soma exists.
If I'm allowed to suggest you something: Make Jason a Belmont, yet make him be born AFTER 2036. He'll still get to know Alucard, Soma et al. albeit not from his childhood. Julius gets to train Curtis Lang AND gets to have a child - who can be trained by Curtis Lang later, since Julius will be too old to do it himself!
Reinhardt Schneider is blood-related to the Belmonts as is Carry Fernandez. Having Jason related to Reinhardt will still keep him in the Belmont family biologically. And yes, he would be able to wield the Vampirekiller in case you are wondering
This is the upside, however. Being a Schneider descendant allows Jason to wield the Vampire Killer with no drawbacks. Making Jason not a direct Belmont descendant on the main canon will surely cause issues about him wielding the whip - namely, the drain of his life force by the whip.