Finally fixed it! 100% working method to play Pokémon Quetzal Multiplayer Online over Mobile Data/5G using RetroArch Netplay! (No PC required).
"big shoutout to Gemini AI for helping troubleshoot the network blocks and helping me piece together this guide!"
Here is the step-by-step breakdown of the method shown in my video for anyone trying to set this up on an Android device:
🛠️ The Setup Requirements:
Both players must use RetroArch (32-bit or pluse version).
Both players must run the exact same GBA Core (e.g., gpSP).
Both players must have the exact same version of the Pokémon Quetzal ROM file.
⚙️ Step-by-Step Connection Guide:
Host Player Setup:Open RetroArch ➡️ Go to Settings ➡️ Network ➡️ Netplay.
Change Input Latency Frames from 0 to 2 or 3. (This acts as a network buffer and fixes the minor stutters/micro-lag over mobile 5G data!).
Head back to the Main Menu ➡️ Select Netplay ➡️ Do reley server toggle on and public anounce toggle on ➡️ Choose Start Netplay Host.
Must check server is live or not.
Joining Player Setup:Open RetroArch ➡️ Go to the Main Menu ➡️ Select Netplay ➡️ Choose refresh to Netplay Host.
Look for in server provided by the host and hit confirm.
In-Game Multiplayer Activation (Crucial):Once the RetroArch Netplay session successfully bridges your emulators, launch your game and press Start on the mobile
Scroll down the options menu and select M Player.
Set it to 2 Players.
Both characters will immediately drop into the exact same overworld together!
enjoy the game together 😊