Uk Citizen with Irish nationality and Japanese girlfriend

Hi all,

Not sure if this is right place for this post but here goes! I (29) am British my dad was born in Ireland, his side is all Irish & my mums is English. So should be straight forward for me to get Irish passport I believe.

I have been dating my Japanese girlfriend (30) for 6 months and we are in love. Her holiday visa ran out so she has had to move to Ireland under a 1 year work visa and will have to wait 6 months to come back to UK, which is fair enough.

We would both like to live in the UK. So I am seeking best way to make this happen. Its pretty clear that we must get married. However its not so clear the best route to go after marriage. I fully understand the long route of her getting an fiancé visa or spouse visa both of which are very expensive etc.

Would it be possible for us to take advantage of my dual nationality and get married in Ireland. So she can become EU citizen then live and work in UK with me for 5 years until she can apply for UK citizenship?

She has already used the 2 year work visa in the UK.

I'm renting a house and have income of 28k a year. So would be able to look after her etc

Any advise would be greatly appreciated!

Cheers

Paddy