Aside from the little reference (in the trainer school to the Slowpoke, Pyumukuku, and Pikachu book, the trio are later seen in both the valley and frozen in Lusamine's room), and the Mimikyu being occasionally there/pika clothes, there really isn't much.
>>34413507Chance of Mimikyu showing up, but instead of actually doing anything it looks at the player then goes back into the trailer. After that encounter, two new dialogue choices show up. The fat guy next to the trailer then asks about it, and then laughs it off. Another dialogue choice appears, and he wonders if inside the trailer is an ultra wormhole that connects it to another dimension.
That's literally it.