Travelling to other countries in Schengen

I have been in Portugal for 5 months, and filled out my paperwork to show ‘expression of interest’ for a working visa here. I am working but just waiting for the SEF appointment, meanwhile, I need to travel to Italy soon - since I have come passed my 90 days does this mean I can’t go to Italy and back to Portugal. Is there anyway around this considering there is nothing I can do about the fact I am just waiting for the SEF appointment in Portugal? So my question is how can I travel to Italy while living in Portugal without being able to get the SEF appointment?

You cannot travel to other Schengen countries while you are waiting for your SEF appointment in this scenario. According to anyone outside of Portugal, you have overstayed and will not be allowed back in, possibly even barred for 5 years. I think you are pursuing a visa according to Article 89.

Where “anyone outside of Portugal” doesn’t include the non-Schengen countries of Ireland and the UK.

All visa related information below was quoted from Visa requirements for United States citizens - Wikipedia

Ireland : Visa not required for US citizens for 3 months. Residence permit for stays of longer than 90 days obtainable after arrival under certain conditions. Up to 90 days if arriving from the Common Travel Area: United Kingdom, Isle of Man, and the Channel Islands (Jersey and Guernsey)

UK : visa not required for US citizens for 6 months. Up to 90 days if arriving from the Common Travel Area: United Kingdom, Ireland, Isle of Man, the Channel Islands (Jersey and Guernsey)

Yes, I know Italy is your preferred destination. But if, when entering a Schengen Zone country, you’re identified as overstaying the 90 days allowed by law, you risk fines and having your history as an Overstayer pop up whenever your passport is scanned when going through immigration control at an airport.