Lots and lots honestly.
The Digimon Kaizer was the result of inheriting part of my brother’s spirit, rather than a ‘dark seed’. I don’t remember the incident with Oikawa well, but I believe that the way he manipulated the other children was in some way copied from what happened to me.
Miyako and I did get married, as we did in canon, but we got divorced shortly there after.
I had a relationship with my (basically unseen in canon) police partner.
Trolls had tails
Lord English wasn’t Caliborn/the Cherubs didn’t exist
I gained the memories of Mindfang when I went through Ancestral Awakening.
I still don’t know exactly what happened in the end, but it was super different than in canon.
No *confirmed* differences yet, but in my timeline Rose Quartz was Pink Diamond