Commission européenne : 

Examine the feasibility of developing a common vaccination card/passport for EU citizens (that takes into account potentially different national vaccination schedules and), that is compatible with electronic immunisation information systems and recognised for use across borders, without duplicating work at national level.

https://ec.europa.eu/health/sites/health/files/vaccination/docs/2019-2022_roadmap_en.pdf

Last update : Q3 2019