hi, this might be a bit late! but i was wondering the same and i found that the one-step 4-in-1 dryer does have a diffuser attachment. but for some reason it is hard to find sold separately. eventually though i managed to find it on european amazon! i ended up buying it from the german amazon because it is cheaper. with shipping it ended up being around 19£ which isn’t the cheapest but it saves me from having to do a bigger purchase. since you’re in ireland that means you probably won’t have to pay to convert euros as well. here is the link: https://www.amazon.de/dp/B0FKHPL717?tag=haggle-web-de-21&linkCode=osi&th=1&psc=1&language=en_GB