It does not have to be an air print printer. It just has to be on the same ethernet network. And shared....The drawback is that you need an AirPrint enabled printer. I can not use my big photo printer even if I can connect it by USB-C wire on the iPad Pro.
I guess it was me that was missing "something". My Mx920 printer was set up with a wired Lan and as a test I switched it to WiFi The iPhone continued to see it as "Canon MX920 Series" location: Study. I went into the printer setting s on my iMac to change the name and Location. The iPhone continued to refer to it as as "Canon MX920 Series" location: Study. Only when I went to the printer's web page did I see the AirPrint designation and the Bonjour Service Name designation: "Canon MX920 Series" location: Study. I have been using AirPrint all along and did not realize it. So, my apologies.Thanks for the hint Cletus but I have such a shared printer on same LAN and it is not accessible. Either wired with an RJ-45 LAN cable or with a USB cable. Maybe because there are no antennas whatsoever on than printer. Only my wife's little portable printer works over LAN. Do I. miss something?