I paid up for my ESB card before Electroverse supported it. Then the second time travelling to Ireland, forgot the card at home. The ESB app worked instead, to my considerable relief. At the time ESB billed only in Euro; I didn't notice the exact time they switched to billing UK customers in pounds. A check list item for going to Ireland now includes "look in car to make sure ESB eCars card is there."
Their pre-pay with auto-top-up system is clunky compared with paying by ordinary contactless bank payment or by Electroverse, and ESB had recently changed the rules on one trip: every single customer was having to phone the help line to get their payment arrangements tweaked. I felt much better about having been so dumb as to need to phone for help, until I saw the next person, and the next, and then more, all having to do likewise. Moral: it works, but don't hesitate to call the helpline for any difficulty. (That's advice for all other charge point operators, too.)
Your credit doesn't expire, so the prepayment's no problem if expecting to visit again.
Slightly off topic, since nothing to do with charging a battery: the video toll on the Dublin ring road motorway can be signed up to beforehand as a visitor, with a limited-time account. If you're likely to go that way, it saves the risk of being charged a penalty for not paying on time. Have your credit card handy for the many other motorway toll points. Tolls are small but most motorways and some modern main roads have them.