https://wccftech.com/new-ipad-air-and-ipad-mini-feature-esim-support-for-a-seamless-wireless-experience/

Both iPad Air 3 and iPad mini 5 feature eSIM support, allowing cellular users to stay connected wherever they are.

Apple’s transition to eSIM is a very interesting one. It allows iPhone or iPad users to register themselves to a cellular network by simply scanning a QR code. This was a feature that was exclusive to the iPhone XS, iPhone XS Max, iPhone XR and the new iPad Pro tablets. Now though, Apple is bringing the party to a new set of devices, namely the iPad Air and iPad mini.