Xerneas

Xerneas = is Pokemon dex #716 (Pokemon Legendary)

Opendex
= Pokemon you already have/registered in your Pokedex, displayed as an image with the Pokemon's details

Non Opendex
= Pokemon you don't have/not registered in your Pokedex, shown as a black shadow (meaning you've seen it in raids/gyms) or just the Pokedex number

Trade Requirements for Opendex
1. Must have 100 Stardust
2. Must have the Pokemon registered in your Pokedex

Trade Requirements for Non Opendex
1. Must have 100 Stardust
2. Still a shadow or you don't own the Pokemon yet

Note: Tip for Non Opendex (Legendary Pokemon/Shiny Pokemon) – Willing to become friends until Ultra Friend to reduce Stardust cost (80,000 Stardust). If willing, buy the cheapest or your favorite Opendex Pokemon from Wantau Store, then message the seller to request a 30-day friendship (Ultra Friend).

How to Trade Opendex or Non Opendex? Check the link below: