Generally you make a will in the jurisdiction in which your estate is going to be administered, which is going to be the place where the bulk of yoru assets are located. If you have immoveable assets like land in more than one country you may be advised to make separate wills in relation to e.g. your Spanish estate and your Irish estate (or your Spanish estate and the rest of your estate, most of which is in Ireland — the latter will would be made in Ireland).
Making a will is a forward-looking exercise — where will your assets be located when you die? This is speculative, since you don't know when you will die and you don't know what may happen between now and then, but you can think about what is likely or about what you intend or hope.
Your daughter is, I'm guessing, young and she seems to be internationally mobile. The only asset you mention is her Australian bank account. She has no other savings and no investments? No insurance policies?
If she plans to remain long-term in Korea and settle there, then it's likely that any assets she acquires in the future will be in Korea. I would suggest a Korean will. Her beneficiaries will probably have to get it admitted to probate in Australia in order to access her bank account there, which will be a bit of a palaver, but not impossible and not that uncommon in practice. Plus, if she does settle in Korea, by the time she dies she may no longer have an Australian bank account, or it may not be a signficant asset.
If she is still open to travelling to other countries and doesn't know where she will settle, then I suggest an Irish will. In due course she can replace it with a will in the country where she settles.
I'm assuming that there are know relevant factors that you have omitted from the OP — e.g, if she had a partner or children or next of kin other than yourself you would have mentioned them and the jurisdiction in which they live.