For Irish firms looking for guidance on how to interpret elements of MiFID II, a good starting point would be the many policy statements issued by the FCA. The Central Bank expects that MiFID projects will be well underway and Irish firms will have a comprehensive MiFID II heatmap in place.
PS17/14: Markets in Financial Instruments Directive II implementation – Policy Statement II
https://www.fca.org.uk/publications/policy-statements/ps17-14-mifid-ii-implementation