Android
Add a Printer by IP Address auf Android
Android relies on the Default Print Service to scan the local network for printers over Wi-Fi Direct or mDNS. Printers on a wired connection, a fixed IP, or behind certain router settings often do not respond to that broadcast, so they never appear in the automatic list.
Adding the printer by IP address avoids the discovery step entirely and talks to the device directly, as long as it sits on the same network.
Where to find the option
Go to Tap on Settings ➔ Tap on Connected devices ➔ Tap on Connection preferences ➔ Tap on Printing ➔ Tap on Default Print Service. Open Open the Menu and choose Tap on Add printer, then Tap on Add printer by IP address. Enter the printer's IP address and confirm with Add.
If the printer still does not respond after adding it this way, the model may need a dedicated print service from the manufacturer instead of the generic Default Print Service. That is more likely with older or business-grade printers that use proprietary print protocols.