But how disable shortcut?

event() - no.

I think event is first passed through event filter chain, then to event() and finally to specific event function:

event
|
event filter (n) -> event filter (n - 1) -> ... -> event filter (0) -> event() -> keyPressEvent(), where event filter (n) is latest installed event filter

I cannot catch this sequence at event filter (n) level so it's obvious I won't catch it at event() level.