I've lived in London, Zurich and Sydney. I've noticed on here NI young people frustrated by the place, for more-or-less the same reasons I had originally left. There have been changes to working holiday visas in recent years, with it now being possible to go to Australia, New Zealand and Canada for up to three years.
Not including places you'd have EU free movement on using an Irish passport, there are working holiday visas in these places:
UK Passport: Andorra, Australia, Canada, Hong Kong, Japan, Monaco New Zealand, San Marino, South Korea, Taiwan, Uruguay.
Irish Passport: Argentina, Australia, Chile, Hong Kong, Japan, New Zealand, South Korea, Taiwan, USA.
United States is bit of an involved topic. There's multiple programmes, with detail here:
https://www.usit.ie/destinations/usa/
Separate to all of this, Canada's trade agreement with the EU has an 'Independent Professionals' work permit category for some occupations. At the the time UK left EU, Canada agreed to roll over that agreement for the UK.
This is the page relevant to Irish passport holders:
UK passport holders:
In addition, EU free movement rights extend to the nine 'Outermost Regions' (but not other EU external territories). This includes Canary Islands:
https://en.wikipedia.org/wiki/Special_territories_of_members_of_the_European_Economic_Area
by BorderTrader
1 comment
Canada also offers working holiday visas to Irish citizens, not just UK citizens – and **explicitly permits** dual citizens to avail of it twice.
https://ircc.canada.ca/english/helpcentre/answer.asp?qnum=1337&top=25