https://www.epo.org/en/service-support/faq/applying-patent/patent-prosecution-highway-pph/overview-pph-procedure/one

One of the requirements is that substantive examination of the EP application for which participation in the PPH programme is requested has not begun. How can I find out whether examination has begun?

The act starting examination is defined in the OJ EPO Notice dated 29 January 2013, OJ EPO 2013, 153. In particular, attention is drawn to page 155 of the above-mentioned notice.

To find out whether the substantive examination has started in a specific file, the examination starting date is visible for unpublished applications only at the request of the applicant or his representative or by inspecting the file using the MyEPO. In MyEPO, the date will be visible on Form F2095.

In published files, you may view these entries in the 'All documents' section of the 'European Patent Register'.