These would not be suitable for EI; those it has on order are A321NeoLR aircraft - different engines and longer range. The Monarch ones are also IAE V2500 powered, whereas the EI ones are CFM 56 powered, so they'd be unsuitable for the short haul fleet either.
Plenty of CFM56 powered aircraft out there, if they want them, but I believe that the plan is to operate DUB-European hub-DUB sectors (e.g. LHR, AMS, BRU, CDG) svces with the new A320s from next year/2019 and that will maximise utilisation and connectivity.