So I just finished Episode 4 and realize now there's only Xiera at the bridge. I would really like to have the other characters back there so it doesn't look so empty. I tried rewatching story from previous chapters (including main story and unread side story), but none of them work. Is there any method?

This is a question that extends to a broader set of questions about continuity snapshots.

At various story points, the NPCs comment on the ongoing story in ways that are often interesting lore. For example, Zeno has a few interesting lines about Melfonseana's arc, Fourie and a couple other NPCs mention their place in the new ARKS organisational structure only early in Episode 4 (I know which branch she is in - do you? If you missed it, you can't find out now), and several characters only make temporary appearances on the ship in the first place. I think even Quna can be spoken to once or twice prior to Episode 4.

These are all missable conversations in a game that is already missing item descriptions on Global. Moreover, anyone who ever does more than one story quest at a time will miss some of what they have to say. The ability to go back and find what certain characters said at different times would be quite useful, you know?

short answer: there's no way to bring Hitsugi, kohri and Enga back in episode 4

however Hitsugi will appear in the other 2 episodes

Wrong, just load a cutscene from earlier in the story when she was on the ship, and bam, she's on-board.

By loading cutscenes you mean rewatch the earlier story quest? I tried side story and main story from earlier chapter (6&7), but they're still not there and Xiera is still saying her line after chapter 8

@Anarchy-Marine you can try that to see it doesn't work, because the duel is there the story will be locked to that point

@Jamesmor There is literally a menu option, that you have to manually select to load in older scenes. It's a filter option, so that you can either chose to see all scenes, or only the scenes you have yet to complete.

@AmakawaHikaru Also, that's weird, because I was able to do that with episodes 1-3, and I was able to get Gettemhult to load back in.

@Anarchy-Marine you can do that in episode 1-3 when you don't have any story part to do but like I said when you have the duel there it will lock the story in that part, unless you finish the duel with Phaleg you can't change the part of episode 4 and I already tried that choosing the part right before Mother fight that has everyone in the bridge

@Jamesmor So just finish the duel. It's super easy. (Laughs quietly to self maniacally)

Also, that's pretty stupid to lock it like that. Not everyone can beat her, even with the best gear currently available.

@Anarchy-Marine even with future gear many not gonna be able to win against her, that's also why I said that Hitsugi will appear in the other episodes

@Jamesmor Wall to be fair, I didn't know that it locks the thing up, because of a duel. Thats pretty lame.

@Anarchy-Marine the same happens in every episode if you have any part to do it will lock you in that part, you can only change the part of the episode when you don't have any part to do

@Jamesmor Ah so it's the duel that's locking the chapter? Makes sense I guess. Wasn't thinking about it since it's not part of the main story.

Wait, if you redo earlier story scenes it does reset lobby state to that point in time?!

I specifically tested for that in the past... I'll try again now. If it does work, my previous post could be disregarded and this would be fantastic news.