Hello Declan
As you will have a euro account in Ireland would it not be cheaper if you transferred 700€ on set day of month by a standing order by your irish bank or Sabadell will do this with no fee and no transfer exchange rate by direct debit. Then next day transfer back by a standing order with Sabadell and you would have a fee free account. You would have to do it in person in Spain but its done by many to overcome fees. I too had same problem with BBVA, told go into bank by helpline but branch said couldnt set up account with a NIE. Bankia too, but could have opened in branch with smaller fee than Sabadell but wasnt happy with it.
Regards
Pauline