Most countries in Europe allow sales of CBD. You can also buy CBD in Ireland but its not always clear what is legal. CBD comes from the cannabis plant and there are many potential health benefits claimed. However because of the potential for THC levels in CBD there are strict guidelines to selling it in Ireland.
You can get CBD from hemp or marijuana plants. Hemp has less THC but because its still a cannabis plant there is public concern when extracting CBD. CBD is not legal for medical use in Ireland yet unfortunately. Although there are certain very specific conditions Doctors can prescribe it for. So there is still gray area but if the THC level is below .02% it is legal in Ireland.