The version 1.3.0 patch for Pokemon Brilliant Diamond and Shining Pearl (BDSP) unlocks trade at the Global Wonder Station (GWS). In order to use the Global Wonder Station’s features, you need a Nintendo Switch Online subscription. The patch is live now.
The Global Wonder Station is in Jubilife City, though players could not enter it at launch. However, with version 1.3.0, the patch notes state that it is now possible to trade Pokemon on the internet through the Global Wonder Station, which implies Wonder Trade is now possible.
With Wonder Trade, you randomly trade with another trainer, which adds an element of gambling to the process. Aside from opening up the Global Wonder Station and an Arceus cutscene (for players with Pokemon Legends: Arceus), the patch provides small quality-of-life upgrades. However, the patch does not go into them in detail.
You can also obtain Arceus as a playable Pokemon. You will first need to beat both Brilliant Diamond or Shining Pearl and Pokemon Legends: Arceus. After getting version 1.3.0, you get an Azure Flute from your room and use it at Mount Coronet’s Spear Pillar.
Version 1.3.0 for Pokemon Brilliant Diamond and Shining Pearl is live now with Global Wonder Station Trade. Pokemon BDSP is available worldwide on the Nintendo Switch.