https://www.fantasy-ireland.com/Celtic-dragons.html
I think the dragons in Wales were fiercely persecuted by the crazy knights for their valour. So, some dragons escaped to Ireland for a quiet life of retirement!
Some had fallen in love with the fairies and nimphs. With the help of magic potion, these dragons transformed themselves into other creatures for a more peaceful life of love and families!
(Source: my own psychic reading!)
Cheers.