Trade Pokémon in FRLG with a Real, Unmodded Switch, From Your Own Computer

FireRed and LeafGreen on Nintendo Switch Online trade over local wireless, the same way two real consoles do when they sit next to each other. Nothing about that goes through Nintendo's servers.

So if a Linux machine can speak that wireless protocol, it can pretend to be the second Switch.

That is exactly what frlg-ldn-trade does.

With it you can:

• Trade any Pokémon into your save, in the real Trade Center, with the real animation
• Send Mystery Gift Wonder Cards to your console, and collect the gift from the delivery man

The Switch you play on stays completely stock. No mods, no custom firmware, no soldering.

This guide covers my exact setup: a MacBook (Apple Silicon) running Ubuntu in a VMware Fusion VM, with a €15 USB WiFi adapter.

1. What you need

Hardware

Amazon link: https://link.amazon/B05qVHcIX

The adapter matters. Most WiFi chips cannot do what this needs. Two are proven:

Known not to work: Intel AX200, Atheros AR9271.

Software

• VMware Fusion, free for personal use
• Ubuntu 24.04 LTS, on Apple Silicon you need the ARM64 build (Ubuntu on ARM)
• Your Switch's prod.keys

You need prod.keys dumped from a Switch. The protocol is encrypted and there is no way around it.

The console you play on stays stock, but the keys have to come from somewhere. If you don't have them, this project isn't for you yet.

2. Set up the Ubuntu VM

Install VMware Fusion, then create a new VM from the Ubuntu ARM64 ISO. Defaults are fine. 2 CPUs and 4 GB RAM is plenty.

Once Ubuntu is installed, plug in the Archer T3U and connect it to the VM:

VMware Fusion menu bar > Virtual Machine > USB & Bluetooth > Connect TP-Link 802.11ac WLAN Adapter

Then inside Ubuntu, check that Linux sees it:

lsusb | grep 2357

You should get:

Bus 001 Device 007: ID 2357:012d TP-Link Archer T3U [Realtek RTL8812BU]

And confirm the driver loaded. No driver install needed, rtw88_8822bu ships with the Ubuntu kernel:

lsmod | grep rtw88_8822bu

rtw88_8822bu           12288  0
rtw88_usb              32768  1 rtw88_8822bu
rtw88_8822b           229376  1 rtw88_8822bu

Find the interface name:

iw dev

3. Install the project

sudo apt update
sudo apt install -y git python3-venv python3-pip
git clone https://github.com/Decryptu/frlg-ldn-trade.git
cd frlg-ldn-trade
python3 -m venv .venv
./.venv/bin/pip install -r requirements.txt

Put your keys where the tools expect them:

mkdir -p ~/.switch
cp /path/to/prod.keys ~/.switch/prod.keys

Keep NetworkManager out of the way

This is the step people miss. The project creates temporary network interfaces mid-run.

NetworkManager grabs them and the connection dies with:

[Errno 114] Match already configured

Marking your WiFi card "unmanaged" is not enough. You have to exclude the interfaces by name:

sudo tee /etc/NetworkManager/conf.d/zz-ldn-unmanaged.conf > /dev/null <<'EOF'
[keyfile]
unmanaged-devices=interface-name:ldnclient;interface-name:ldn;interface-name:ldn-mon;interface-name:ldn-tap
EOF

sudo systemctl restart NetworkManager

Check everything

./scripts/preflight_pi.sh

Despite the name, it works on any Linux box, not just a Raspberry Pi. Every line should say OK.

4. Example 1: Mystery Gift

Your computer becomes a Wonder Card distributor. Your save needs Mystery Gift already unlocked.

On Linux, start the host:

sudo -E ./.venv/bin/python -u frlgmg_host.py \
  --gift beast-cutscene \
  --flag-id 1005 \
  --version firered \
  --client-ready-idle-frames 20

Wait for:

Hosting Mystery Gift. On the Switch choose Mystery Gift -> Wonder Cards -> Friend.

On the Switch: Mystery Gift > Wonder Cards > Friend

The console finds the host and pulls down the card. You'll see:

Console identified itself: 'YOURNAME' on FireRed, holding no Wonder Card
Mystery Gift server finished: Wonder Card sent
The console left LDN after confirming Mystery Gift close

Now walk into any Pokémon Center and talk to the delivery man to collect the gift.

Tip: --flag-id is the "receipt" flag. Once a save has received flag 1005, it won't take that gift again. Use a different number (1006, 1007, etc.) to receive it a second time.

5. Example 2: Trading, with Linux as the host

Here Linux runs the group and the Switch joins it.

You need at least two .pk3 files. These are the Pokémon in your computer's fake party.

One of them is what you'll trade away.

On Linux:

sudo -E ./.venv/bin/python -u frlgtrade_host.py \
  PARTY1.pk3 PARTY2.pk3 \
  --version firered \
  -o received.pk3

Wait for:

Hosting. Waiting for the console to join (ssid=..., channel 1).
Hosting Direct Corner. On the Switch choose Join Group.

On the Switch:

1. Go to the 2nd floor of any Pokémon Center
2. Talk to the third NPC (the one on the right), not the middle one. That's the Union Room and it will not see this host
3. Pokémon Wireless Club > Trade Center > Yes
4. Choose Join Group, and pick the group named PkCamp
5. Walk to the trade table and sit down
6. Pick your Pokémon, confirm, and watch the trade

By default the computer offers the second file you passed (PARTY2.pk3). Change it with --slot.

A successful run looks like this:

Trade-room entry complete; exchanging party data.
Party exchange complete; trade selection is active.
Received: #113 (#113)
Saved -> received.pk3 (pk3, 100B)
Save barriers complete; waiting for the Switch menu handoff to finish.
Final party refresh complete; waiting 5 seconds for the trade menu.
Switch CANCEL received; both players cancelled. Leaving the trade menu.
Both players left the room; closing the RFU link.

The Pokémon you received from the console is written to received.pk3.

Leaving cleanly

When the party list comes back after the trade, select Cancel > Yes on the Switch. Both sides then walk out of the room and the link closes properly. Don't just quit the game.

In French

If your game is in French, like mine:

• Club sans fil Pokémon > Centre Troc > Oui
• Rejoindre to join
• Annuler > Oui to leave at the end

6. The other direction

The Switch can host and your computer can join instead:

sudo -E ./.venv/bin/python -u frlgtrade.py --live \
  -o received.pk3 PARTY1.pk3 PARTY2.pk3

Same NPC path on the console, but choose host instead of join, then accept PkCamp when it appears.

Both directions work. Hosting from Linux is the more reliable one, so start there.

7. Things that will bite you

• Never pass --verbose to a live run. Its per-packet logging runs inside a frame-timed loop and the console will drop the connection. Use --capture FILE instead. It's safe.
• Only one run on the radio at a time. Check with ps -ef | grep frlg before starting.
• --client-ready-idle-frames 20 is needed for Mystery Gift on my console. The built-in default leaves the host silent for ~2 seconds and the console gives up after half a second.
• Cross-version trading works. A host advertising --version leafgreen trades happily with a FireRed console. It's just a flag.
• Language doesn't matter. My French FireRed accepted an English Wonder Card without complaint.
• Runs sometimes fail halfway. Power-cycle nothing, just start over. It usually works on the next attempt.

8. Credit

This is a fork built on other people's work:

• tornadus, the original trading core and the proof that any of this was possible
• MercuryEnigma, Mystery Gift support and the Raspberry Pi deployment

My fork adds the Switch-hosted (joiner) direction and TP-Link Archer T3U support:

github.com/Decryptu/frlg-ldn-trade

There's a Discord for the wider effort. The long-term goal is things like an unofficial GTS and online battling for these games.

Nothing here touches Nintendo's servers, and the console never leaves stock firmware. It's two devices talking to each other over local wireless. One of them just happens to be a laptop.