The guidance MDCG 2019-15 includes a comprehensive overview of the manufacturers‘ obligations for all Class I products.
It also gives some further clarification concerning the "Authorized Representative":
A manufacturer with a registered place of business outside the Union will designate a sole authorised representative, at least per each generic device group, according to a written mandate.
At the same time it includes further specifications of the manufacturers' obligations:
The manufacturer should periodically verify whether implementing and delegated acts, common specifications, technical standards and guidelines might be available on the European Commission website.