If print quality drops when using the switch:

: Basic functions are often supported by Windows built-in drivers, but utility software for status monitoring is available through IOGEAR software updates . ATEN (US221A)

However, there’s an important technical reality to note:

If your switch has no chip inside (just physical relays), no driver exists. Try a powered USB hub between switch and printer.

Some older generic models include a small software utility on a mini-CD that enables the hotkey for switching. Troubleshooting & Installation Tips 2-Port USB 2.0 Printer Auto Sharing Switch Drivers Download

Sorry, that is a members only option