Okkkk. I'm kinda lost with this. My first issue is that the next chapter will wrap up the entire story? Cause I played chapter 7 and it feels like they have a way to go to establish some form of hard evidence to take down the competition and expose the corruption and tampering. Unless I'm missing something.
In terms of your part 2, there are three ways I see that you could do it:
1. New game, new characters. I don't think wiping the slate clean with existing characters will work for people. I think it would be better to just trust yourself to be able to come up with new interesting characters.
2. Same Mc, sequel (no wiping slate), new story, new and old Lis. You could do some kind of espionage adventure as
Beast Within suggested. Possible Mc gets pulled into some CIA investigation in the industry, whatever and he has to change job/locations and meet and get close to new people (Lis). You could also have him reach out to some or all of the old Lis to help him out. It could get crowded in the Li department though.
3. Self contained alternate reality stories with the same Mc and Lis but with new continuity. Something like the Christmas Specials some devs do where it doesn't fit into the main continuity of the game and is a self contained story. Thing is a lot of players hate or are not too fond of those specials because they feel disposable, Few of them are any good. To make it special you would really have to do it like an alternate take on the main game.
1 or 2 might be your best bet. I'm not sure 3 would work well at all.