MacBook Air printer missing for scanning and sharing

The HP Color LaserJet Pro MFP M479fdw is an Apple AirPrint enabled device.

About AirPrint - Apple Support

I am not quite certain what you mean by "disappeared from my applications" though. Printers don't appear in Applications. Add it to Printers & Scanners as an AirPrint device:

Add a printer to your printer list so you can use it on Mac - Apple Support

You must explicitly choose AirPrint.

What is the vendor and full model name of the particular multi-function printer?

I don’t see tech specs for that printer.

Can you check that model number again?

Maybe LaserJet Pro MFC M479fn, or LaserJet Pro MFC M479fnw?

https://support.hp.com/ie-en/document/c06372746

Semi-related: There was apparently a legal case with a similarly-named model:

https://support.hp.com/ie-en/document/ish_11775540-11775594-16