I think I have read the summaries/general plots for the expansions in the past, but I have long since forgotten the details. The wonderful thing about that game is that making different choices puts a new spin on things. Even with spoilers, experiencing it will be different for me than it was for you.
Also, AC: Odyssey is surprisingly good. My wife plays it when she's frustrated with her paperwork. I watch her assassinate people with a bit of growing fear.
"In the original Carmen looks like a man. The original episodes all end the same, the new one has more characters, they all end differently and the art style is better"