For years, you have been able to buy furniture copies legally from Ireland. Previously it was possible to sell replica designer furniture from England because the copyright law only applied for 25 years. In 2016 it was set to 70 years as in other European countries. However, Irish copyright law is still unchanged.
Original vs. replica furniture - is there a difference?
If you are looking for replica furniture at websites in English or other sites, you can probably get an impression of the company that sells them. There is obviously a big difference between various options, and it is, therefore, difficult to say something definite about replica design. Several former dealers from England have been selling furniture in a really good quality while you can be sure to find other distributors from e.g. Asian countries, that sell chairs and lamps in very low quality.
It is thus advised, to check out reviews online and use common sense. There will probably always be a slight difference between an original and a replica, but often it will only be furniture connoisseurs who will notice it. For example, a furniture expert once wrote a review of a copy of an Arne Jacobsen chair, and his only note was that the seams were not quite as fine in some places.
One of the key factors is whether leather, wood and other materials are similar to the one used in the originals. For example, there are many different qualities of the leather and the same with wood where oak typically is the best. Therefore, read the product specifications and compare with the original furniture.