A friend of mine pointed that at the end of the trailer, it appears that Cayde is being carried by the Eco Stranger. It may be a bit of a stretch, considering we can't see their face, but the cloak looks pretty similar to the one the Exo Stranger is wearing on the grimoire card from D1. Exo Stranger carrying Cayde (???): https://imgur.com/a/ghocYi9 Exo Stranger Grimoire Card: https://imgur.com/a/WCBtdyN