0:03: N's Castle? Though it doesn't look like it. Also who are on the staircases? If it is N's Castle maybe the Unova Elite Four. On does look like Shauntel's collar.
0:09: So is this the story about how the Brass/Burned Tower burned down and the Legendary Beasts were created or is this the scene where the player meets them and they run off?
0:10: Red confronting Perfect Zygarde? Where is this taking place? I'm going to assume this is the same cave we saw in the beginning with the hole shooting out light. Judging by the rivers we saw at 0:01 and the wooden planks in the cave maybe it's Terminus Cave? But what's Red doing in Kalos?
0:14: This has to be post the events of Gen I as Giovanni is wearing his "exiled" trench coat.
0:17: Why are you hiding his face? It's Red. The clothes are kind of a dead giveaway (unless they want to pull some kind of surprise reveal though that could easily turn into something stupid if not handled right).
0:19: A Looker story which involved Poke SWAT using a Machamp to burst through a wall. This would have to be a story outside of the games as he operated alone when you meet him in the games. And the only side story involving Looker I can imagine fans wanting to know is the one involving how he lost Croagunk.
0:26: Guessing this is connected to the Red encountering Zygarde story. Say, does Pikachu look a bit roundish?
0:30: Since the Red Gyarados was still in the Lake of Rage and Lance was nearby during that part of Gen II's events I'm going to guess this scene shows Lance attempting to defeat/catch the Red Gyarados before the player arrived?
0:36: Blue's Elite Four Challenge, that should be fun to see. And we'll finally get the answer whether there was no Champion before Blue defeated the Elite Four.
0:38: Guessing this is part of the Looker story, we saw Poke SWAT with an Arcanine and it's infiltrating a building like how Machamp was used to break through the wall.
0:39: Buck & his Claydol battling Heatran.
0:42: Cheryl & her Chansey must have an adventure in the Old Chateau.
0:43: More of Blue's Elite Four Challenge (Blue, did you really need to slam Bruno's Machamp into him?). And I just now realized that, in addition to being a balanced team, Blue's team also was made to defeat the Elite Four. Rhydon/Arcanine/Exeggutor for Lorelei, Pidgeot/Alakazam/Exeggutor/Blastoise for Bruno, & Pidgeot/Alakazam for Agatha. Nothing really for Lance but Blue's team is varied enough it can take on his Dragon-types (plus Gyarados and Aerodactyl).
0:44: Regigigas in Snowpoint Temple.
0:54: I'm going to guess this is where the episode of Blue's Elite Four Challenge ends. Also this is a different voice for Blue than from Origins (who was voiced by Lucien Dodge, unless he changed the way Blue sounds for some reason).