Xerox B210 works properly from iPhone but from MacBook air. Same network, of course. "Encryption Credentials expired"

Try reseting the Mac's printing system.

see > Reset the printing system on your Mac to solve a problem - Apple Support

Thanks for posting in the Apple Support Community pappelod,

The following steps address issues you might encounter with wireless network printing:

• Make sure that you have the latest version of macOS. Choose Apple menu  > System Settings, then click General  in the sidebar. Click Software Update on the right, then install any software updates listed.

• Try connecting the AirPrint printer to your Wi-Fi network using a cable for direct connection or through bridging. See Bridge virtual network interfaces. The printer may then be able join the Wi-Fi network and work wirelessly.

• After turning on your printer, wait a few moments before trying to print. After powering up, some printers might take a minute or two before joining the network.

• If you’re using an AirPort Base Station or AirPort Time Capsule, connect it to your AirPrint printer using the Ethernet LAN port or through your Wi-Fi network. You can’t use AirPrint to print to a printer that’s connected to the USB port of an AirPort Base Station.

• Check with your printer’s manufacturer to see if any updates are available for your printer model.

Print wirelessly from your Mac to your printer

We hope this helps!