Is there any Event Pokemon that can NOT have some sort of gift ribbon?

Question

I want to trade some event Pokemon over GTS negotiations. I konw one is the victini caught on liberty Island.

Answer 1

Any Pokemon that is not directly given at an event cannot have an Event ribbon. So, the Victini that is received directly from the WiFi mystery gift has a ribbon, while a Victini caught at Liberty Island from an Event item cannot, as it you didn't receive it directly from an event.