Not much use, but the only 'good' (as in posh or non-fast) Japanese restos in Ireland have closed down over the years. For a while they were the only ones in the country.
There used to be 2 Ayumi-ya restos - one in Newtownpark Avenue in Blackrock and a second in Baggot Street. The family that owned them now own Aya, but it is run on different lines.
There was also a most excellent place (with a Michelin star) down in west Cork - Shiros, but a) it's not in Dublin and b) it is closed down.
In Dublin the only ones I know of are Wagamama and Yamamori. There are a few other asian fusion places that do some Japanese, but not a great range. There are also a few Teppan places around (Yo Thai! is the chain I think with one in Donnybrook, Mount Merrion & Howth I think) and the one in Donnybrook at least has a sushi chef, but since I don't eat sushi I can't comment on the quality.
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