This must be one of the most frustrating things in Opera GX.
With all the "freedom" and "customization" ads that Opera Marketing Team provides us - telling us how versatile and customizable this browser attempts to be - it is unbelievable that something as simple as disabling/changing the Search engines keyboard shortcuts is not available to us.
It has been over 3+ years Opera. Please, allow us to truly customize this option out of existence.