The difference visually between the two is the RC2 has a built in screen and two adjustable antennas.  My question relates to the adjustable antennas.  Do they give a superior advantage to the RC2 over the RC2N in signal strength and distance?  

Hi there. Thank you for bringing this query to us. The DJI RC-N2 antennas have been upgraded to 2T2R (two antennas for transmitting and two antennas for receiving while the DJI RC 2 uses 2T4R (six antennas) with improved processor performance for the smooth operation of the system and app. Should you have other inquiries, please don't hesitate to reach us. Thank you for your valued support.

Is it correct that the rc-n2 only works with the air3?

Yes, both the RC2 and RCN2 use OCUSYNC 4.0 only.  No other drone uses 4.0 except the Air3.

socrbob Posted at 8-10 18:30
Is it correct that the rc-n2 only works with the air3?

Hi, socrbod. You are correct. O4 is DJI's latest generation of video transmission technology, which enhances the transmission distance and improves the stability of the transmission connection in complex environments through the use of multi-antenna technology and upgraded communication algorithms. DJI Air 3, DJI RC-N2, and DJI RC 2 support the latest O4 video transmission technology. By using the complete devices with O4 technology, you can enjoy a smoother and more reliable image transmission experience.