1) Wing it. Online check-in, present passports with baggage (if necessary) and don't say a word.

I travel on what is effectively a nickname different to my passport names. It's close enough not to cause an issue. And that includes Aer Lingus. Ringing up and getting lots of comments on your booking is perhaps asking for trouble, however.

I would ensure, however, that the API stuff in the booking is correct. There is a pattern match on names, with some variations allowed, so even that isn't rigorous.