You can spoof flipper0 to act as an Apple AirTag by editing gap.c file in firmware and send data to be advertise simulating AirTag package.
After all these changes flipper0 can still connect normally by Bluetooth without issues.
Info
Just replace gap.c with the modified one.
Works with Official Flipper Firmware but should work with unleashed, RogueMaster too
You need to sniff the nfc registration data in 14443a protocol between a real AirTag and Iphone process and change the advertise data. (You need new unpaired AirTag)