I'm gonna be the unpopular opinion and say I don't even think Alien Isolation needs a sequel. For it to be too concrete in its presence in canon it can sabotage itself into being considered less, if you get what I'm saying. I've come to grow into accepting personal choice in picking canon is the best option. But that's just personally because I believe A. Ripley died in the vacuum of space and probably got replaced by an Android on her scheduled return, a bit of a clever retcon as to why she never married or had children and died fairly early. It's anyone's guess I like it that way but I'm a masochist.
If they were to do a sequel, this is what I would do. I would love the idea with a genesis in the ghost ship of the MSV-7760 Torrens floating out there nebulous in sub-light speed before it runs out, someone intercepts it, you get the idea. With all the naval/spaceflight parallels, the idea of a huge hulking ghost spacecraft fairly larger than the narcissus with some deadly secrets interesting. They could easily follow parts of Gibson's Alien III script from there (obviously not the genetic engineering parts) . An authority anchor for some region, (Marshal Border Patrol?, maybe Marshal would be less trope than Marines for the millionth time), pick it up, clamp it, board it, and shit gets sticky quick. I don't think establishing a blank slate character would be too invasive, at that point it would be its one thing, with mostly the boarding incident in the background, just having things on station deteriorate. And Weyland-Yutani like Wiley Coyote go hunting again and its a race against time before they arrive, maybe the protag comes across communications saying they want to abduct everyone in proximity to the infection for study, or maybe they want to capture an alien and blast the station to hell. The idea of a precise time limit after a point in the game, to get done what has to be done sounds very in tune with what Alien is all about. Rushing running and rushing and running.
As for more precise details, I'm not sure. But it's just an idea throwing around IF they decide to go with a 2. I think having Amanda be, in canon dead, is a bit more ominous and gives Burke a bit more sinister edge, or Burke was just playing off records. Who knows. This is just where I'd like to see them go. And I'm sure not everyone would agree with it.